RBSE Solutions Class 6 Science Chapter 7 Temperature and Its Measurement

Temperature and Its Measurement Class 6 Questions and Answers

Temperature and Its Measurement Class 6 Question Answer - InText

 

Question 1. Can it always be correctly judged, that a person has fever, only by touching the person?
Answer: No, we cannot always trust our sense of touch to tell correctly if someone's body is hot or cold. Our hands can feel things differently based on how hot or cold our own hands are. Therefore, touch is not a very reliable way to check for fever.
In simple words: No, you cannot always tell if someone has a fever just by touching them. Our touch is not always accurate.

🎯 Exam Tip: Always remember that subjective senses like touch can be misleading; scientific measurement is needed for accurate results.

 

Question. The normal temperature of a healthy human being is close to
(i) 98.6 °C
(ii) 37.0 °C
(iii) 32.0 °C
(iv) 27.0 °C
Answer: (ii) 37.0 °C
In simple words: The normal body temperature for a healthy person is about 37.0 degrees Celsius.

🎯 Exam Tip: Know the normal human body temperature in both Celsius and Fahrenheit scales, as questions might use either.

 

Question 2. 37 °C is the same temperature as
(i) 97.4 °F
(ii) 97.6 °F
(iii) 98.4 °F
(iv) 98.6 °F
Answer: (iv) 98.6 °F
In simple words: When it's 37 degrees Celsius, it's the same as 98.6 degrees Fahrenheit. These are just two different ways to say the same temperature.

🎯 Exam Tip: Be familiar with the conversion between Celsius and Fahrenheit for normal body temperature values, as these are frequently asked.

 

Question. Fill in the blanks :
(i) The hotness or coldness of a system is determined by its
(ii) The temperature of ice-cold water cannot be measured by a thermometer.
(iii) The unit of temperature is degree
Answer:
(i) Temperature
(ii) Clinical
(iii) Celsius
In simple words: We find out how hot or cold something is by its temperature. Clinical thermometers are not made for very cold water, and Celsius is a common way to measure temperature.

🎯 Exam Tip: Understand the basic concepts of temperature and the appropriate tools for measuring different temperature ranges.

 

Question 4. The range of a laboratory thermometer is usually
(i) 10 °C to 100 °C
(ii) -10 °C to 110 °C
(iii) 32 °C to 45 °C
Answer: (ii) -10 °C to 110 °C
In simple words: A laboratory thermometer can measure temperatures from 10 degrees below zero Celsius up to 110 degrees Celsius. This wide range makes it useful for many science experiments.

🎯 Exam Tip: Remember the typical temperature ranges for different types of thermometers (clinical, laboratory) to distinguish their uses.

 

Question. Who do you think followed the correct way for measuring temperature?
(i) Student 1
(ii) Student 2
(iii) Student 3
(iv) Student 4
Answer: (ii) Student 2
In simple words: Student 2 is showing the right way to measure temperature with a thermometer. The bulb must be fully in the liquid and not touching the bottom or sides of the container.

🎯 Exam Tip: For accurate temperature readings, ensure the thermometer bulb is fully immersed in the substance and does not touch the container's sides or bottom.

 

Question 6. Colour to show the red column on the drawings of thermometers (Fig. 7.7) as per the temperatures written below:
Answer: The answer would involve drawing on the provided diagrams (Fig. 7.7) to show the red column at 14 °C, 17 °C, and 7.5 °C. For 14 °C, the red column would be above 10 and below 20, slightly below the halfway mark. For 17 °C, it would be higher, close to 20. For 7.5 °C, it would be just below 10, past the 5 mark.
In simple words: You need to draw the red line inside each thermometer picture (Fig. 7.7) to match the temperature numbers given. Make sure the red line reaches the correct height for 14°C, 17°C, and 7.5°C.

🎯 Exam Tip: When drawing thermometer readings, pay close attention to the scale markings and estimate the position of the liquid column accurately.

 

Question 7. Observe the part of thermometer shown in Fig. 7.8 and answer the following questions :
(i) What type of thermometer is it?
(ii) What is the reading of the thermometer?
Answer:
(i) This is a clinical thermometer. Clinical thermometers are specially designed to measure human body temperature.
(ii) The reading of the thermometer is 37 °C. The mercury column has risen to the 37-degree mark on the Celsius scale.
In simple words: The picture (Fig. 7.8) shows a clinical thermometer. It is reading 37 degrees Celsius.

🎯 Exam Tip: Identify different thermometer types by their appearance and typical scales, and practice reading temperatures accurately from diagrams.

 

Question 8. A laboratory thermometer is not used to measure our body temperature. Give a reason.
Answer: A laboratory thermometer is not used for measuring body temperature because its temperature range is generally from -10 °C to 110 °C. This range is much wider than the normal human body temperature range, making it less precise for body temperature. Also, it doesn't have the kink (constriction) that a clinical thermometer has to hold the mercury level, so the reading changes quickly after removal.
In simple words: We do not use a laboratory thermometer to check body temperature. It has a very wide range and does not hold the reading, so it is not right for checking fever.

🎯 Exam Tip: Focus on the specific features and temperature ranges that differentiate clinical and laboratory thermometers when explaining their uses.

 

Question 9. Vaishnavi has not gone to school as she is ill. Her mother has kept a record of her body temperature for three days as shown in Table-
(i) What was Vaishnavi's highest recorded temperature?
(ii) On which day and at what time was Vaishnavi's highest temperature recorded?
(iii) On which day did Vaishnavi's temperature return to normal?

Answer:
(i) Vaishnavi's highest recorded temperature was 40.0 °C. This temperature indicates a significant fever.
(ii) Vaishnavi's highest temperature was recorded on the first day at 7 pm.
(iii) Vaishnavi's temperature returned to normal on the third day. By the end of day three, her temperature was within the normal range.
In simple words: Vaishnavi's temperature was highest at 40.0 °C on Day One at 7 pm. Her temperature went back to normal on Day Three.

🎯 Exam Tip: Carefully scan all data points in a table to find maximum, minimum, or specific trends requested in the question.

 

Question 10. If you have to measure the temperature 22.5 °C, which of the following three thermometers will you use (Fig. 7.9)? Explain.
Answer: To measure a temperature like 22.5 °C accurately, we need a thermometer that can measure to at least 0.5 °C. Thermometer (b) in Fig. 7.9 is the most suitable because its smallest divisions allow for a 0.5 °C measurement. Thermometers (a) and (c) might have larger divisions, making it hard to get an exact 22.5 °C reading.
In simple words: We would use thermometer (b) from Fig. 7.9 because it can measure in half-degree steps, which is needed for 22.5 °C.

🎯 Exam Tip: Choose a thermometer based on its smallest division (least count) to ensure the required precision for the measurement.

 

Question 11. The temperature shown by the thermometer in Fig. 7.10 is
(i) 28.0 °C
(ii) 27.5 °C
(iii) 26.5 °C
(iv) 25.3 °C
Answer: (ii) 27.5 °C
In simple words: The thermometer in Fig. 7.10 shows that the temperature is 27.5 degrees Celsius. Look closely at the markings to see where the liquid level stops.

🎯 Exam Tip: When reading a thermometer, always check the major markings and the number of small divisions between them to determine the exact value.

 

Question 12. A laboratory thermometer has 50 divisions between 0 °C and 100 °C. What does each division of this thermometer represent?
Answer: If a laboratory thermometer has 50 divisions between 0 °C and 100 °C, then each division represents a temperature change of 2 °C. This is calculated by dividing the total temperature range (100 °C - 0 °C = 100 °C) by the number of divisions (50). This means the thermometer can measure in steps of 2 degrees.
In simple words: Each small line on this thermometer means 2 degrees Celsius. You get this by dividing the total degrees (100) by the number of lines (50).

🎯 Exam Tip: To find the value of one division on a scale, divide the total range by the total number of divisions within that range.

 

Question 13. Draw the scale of a thermometer in which the smallest division reads 0.5 °C. You may draw only the portion between 10 °C and 20 °C.
Answer: The answer requires a drawing of a thermometer scale. Imagine a line with markings for 10 °C, 11 °C, 12 °C, up to 20 °C. Between each whole degree mark (e.g., between 10 °C and 11 °C), there should be one smaller mark exactly in the middle. This middle mark represents 0.5 °C. So, you would have 10, 10.5, 11, 11.5, and so on, up to 20 °C. A typical drawing would also include the word "Thermometer" below the scale.
In simple words: You need to draw a part of a thermometer scale from 10°C to 20°C. For every whole number, also draw a half-mark in between, like 10.5°C, 11.5°C, etc.

🎯 Exam Tip: When drawing scales, ensure consistent spacing for divisions and clearly label at least the major numerical marks.

 

Question 14. Someone tells you that she has a fever of 101 degrees. Does she mean it on the Celsius scale or Fahrenheit scale?
Answer: If someone says they have a fever of 101 degrees, they almost certainly mean it on the Fahrenheit scale. Normal human body temperature is around 37 °C (which is 98.6 °F), so 101 °F is a common fever temperature. 101 °C would be an extremely high and life-threatening temperature, far above the boiling point of water. This is why doctors usually use Fahrenheit for body temperature.
In simple words: A fever of 101 degrees means 101 degrees Fahrenheit. If it were Celsius, that would be a dangerously high temperature.

🎯 Exam Tip: In daily life, human body temperatures are typically discussed in Fahrenheit in many regions, while Celsius is common for environmental and scientific measurements.

RBSE Class 6 Science Chapter 7 Important Questions

Multiple Choice Questions

 

Question 1. The SI unit of temperature is-
(a) Celsius
(b) Fahrenheit
(c) Kelvin
(d) All of the options
Answer: (c) Kelvin
In simple words: The official scientific unit for measuring temperature is Kelvin.

🎯 Exam Tip: Remember that while Celsius and Fahrenheit are common, Kelvin is the SI (International System of Units) unit for temperature.

 

Question 2. Which of the following is used in thermometers?
(a) Lead
(b) Mercury
(c) Silver
(d) Copper
Answer: (b) Mercury
In simple words: Mercury is a common liquid used inside many thermometers because it expands and contracts evenly with temperature changes.

🎯 Exam Tip: Mercury's ability to expand and contract uniformly with temperature makes it ideal for thermometers, but its toxicity is a concern.

 

Question 3. The special thermometers used during the Covid-19 pandemic is called-
(a) Doctor's thermometer
(b) Mercury thermometer
(c) Room thermometer
(d) Infrared thermometer
Answer: (d) Infrared thermometer
In simple words: During the Covid-19 pandemic, special thermometers called infrared thermometers were used to measure temperature without touching.

🎯 Exam Tip: Non-contact thermometers are valuable for public health as they prevent the spread of infections.

 

Question 4. The body temperature of a person depends on which factors-
(a) Age
(b) Time of the day
(c) Activity level
(d) All of the options
Answer: (d) All of the options
In simple words: A person's body temperature can change based on how old they are, what time of day it is, and how active they have been.

🎯 Exam Tip: Body temperature is not static; it fluctuates based on internal and external factors, which is an important biological concept.

 

Question 5. The human body generally has a temperature range of-
(a) 35°C - 42°C
(b) 32°C - 42°C
(c) 35°C - 45°C
(d) 36°C - 40°C
Answer: (a) 35°C - 42°C
In simple words: The normal temperature range for the human body is usually between 35 degrees Celsius and 42 degrees Celsius.

🎯 Exam Tip: The human body maintains a narrow temperature range for proper functioning; temperatures outside this range can indicate illness.

 

Question 6. The normal temperature of the human body on the Fahrenheit scale is-
(a) 37°F
(b) 98.6°F
(c) 98.4°F
(d) 94.8°C
Answer: (b) 98.6°F
In simple words: On the Fahrenheit scale, a healthy person's body temperature is normally 98.6 degrees Fahrenheit.

🎯 Exam Tip: Be able to state normal body temperature in both Celsius (37°C) and Fahrenheit (98.6°F) for quizzes.

 

Question 7. The thermometer that show' temperature digitally are called-
(a) Laboratory thermometer
(b) Clinical thermometer
(c) Digital thermometer
(d) Maximum-Minimum thermometer
Answer: (c) Digital thermometer
In simple words: Thermometers that show temperature numbers on a screen are called digital thermometers.

🎯 Exam Tip: Digital thermometers are popular because they are easy to read and safe, as they don't contain mercury.

 

Question 8. Is not a temperature scale-
(a) Celsius scale
(b) Fahrenheit scale
(c) Richter scale
(d) Kelvin scale
Answer: (c) Richter scale
In simple words: The Richter scale is used to measure earthquake strength, not temperature. Celsius, Fahrenheit, and Kelvin are all temperature scales.

🎯 Exam Tip: Differentiate between scales used for temperature (Celsius, Fahrenheit, Kelvin) and other scientific measurements (like Richter for earthquakes).

 

Question 9. Generally the minimum temperature that can be measured by a laboratory thermometer is-
(a) 10°C
(b) -10°C
(c) 0°C
(d) 100°C
Answer: (b) -10°C
In simple words: A laboratory thermometer can usually measure temperatures as low as 10 degrees below zero Celsius.

🎯 Exam Tip: Remember the lower limits of laboratory thermometers are often below 0°C, suitable for experiments involving cold substances.

 

Question 10. Who is known as the 'Weather Woman of India"?
(a) Anna Malai
(b) Anna Mani
(c) Sunder Rajan
(d) None of these
Answer: (b) Anna Mani
In simple words: Anna Mani was a famous Indian scientist known for her work in weather instruments, earning her the name 'Weather Woman of India'.

🎯 Exam Tip: General knowledge questions about famous scientists and their contributions are sometimes included in science exams.

Fill in the blanks

 

Question 1. The .................... of a body tells us how hot or cold it is.
Answer: temperature
In simple words: Temperature tells us how hot or cold something feels.

🎯 Exam Tip: Understand that temperature is the physical quantity that quantifies the degree of hotness or coldness.

 

Question 4. Doctors thermometer is used for measursing the .................... temperature.
Answer: human body
In simple words: Doctors use a special thermometer to measure a person's body temperature.

🎯 Exam Tip: Clinical thermometers are specifically designed for measuring human body temperature due to their range and mercury-holding kink.

 

Question 5. Mercury is not used in .................... thermometer.
Answer: digital
In simple words: Digital thermometers do not use mercury; they use electronic sensors.

🎯 Exam Tip: Digital thermometers are safer as they avoid the use of mercury, which is toxic.

 

Question 6. A device that measures temperature is called a .................... thennometer.
Answer: thermometer
In simple words: The tool used to check how hot or cold something is called a thermometer.

🎯 Exam Tip: Ensure correct spelling of scientific terms like 'thermometer'.

True/False

 

Question 1. We should always rely upon our sense of touch to decide correctly whether a body is hot or cold. (True/False)
Answer: False
In simple words: It's false; our sense of touch cannot always correctly tell us if something is hot or cold.

🎯 Exam Tip: Emphasize that scientific measurements are objective, unlike subjective senses like touch, which can be easily fooled.

 

Question 2. For measuring temperature, the clinical thermometers generally use a scale called the Celsius scale. (True/False)
Answer: True
In simple words: Yes, it's true that clinical thermometers mainly use the Celsius scale to measure temperature.

🎯 Exam Tip: Know that clinical thermometers commonly use both Celsius and Fahrenheit scales, but Celsius is often the primary scale taught.

 

Question 3. The temperature of every person may not be 37.0°C (True/False)
Answer: True
In simple words: It is true that not everyone will have exactly 37.0°C body temperature; it can vary slightly.

🎯 Exam Tip: Normal body temperature is an average; individual temperatures can vary slightly and still be healthy.

 

Question 4. We can use laboratory thermometer to measure the temperature of a human body. (True/False)
Answer: False
In simple words: It is false to use a laboratory thermometer for measuring human body temperature.

🎯 Exam Tip: Always use the correct type of thermometer for its intended purpose (clinical for body, laboratory for experiments).

 

Question. Match the items in Column-I with Column-II:

Answer:In simple words: This table matches different types of thermometers with the substance they use or how they work. For example, laboratory thermometers might use alcohol, and digital ones use heat sensors.

🎯 Exam Tip: For matching questions, understand the key characteristic or working principle of each item to pair them correctly.

 

Question 2. Match the items in Column-I with Column-II:

Answer:In simple words: This table links specific temperatures to what they represent. For example, -273.15°C is absolute zero, 37°C is a healthy adult's temperature, 39°C indicates a fever, and 25°C is typical room temperature.

🎯 Exam Tip: Memorize important temperature benchmarks like absolute zero, normal body temperature, and typical room temperature for quick recall.

Very Short Answer Type Questions

 

Question 1. Name the instrument by which temperature can be measured?
Answer: Temperature can be measured using an instrument called a thermometer. Thermometers come in different types, each suited for specific measurement needs. The word 'thermometer' itself tells us it's a 'heat-meter'.
In simple words: A thermometer is the tool we use to measure temperature.

🎯 Exam Tip: Make sure to spell 'thermometer' correctly as it's a fundamental term in this topic.

 

Question. How many types of thermometers are generally used to measure temperature? Name them.
Answer: Generally, two main types of thermometers are used to measure temperature: clinical thermometers and laboratory thermometers. Clinical thermometers are for body temperature, while laboratory thermometers are for general experiments.
In simple words: There are two main kinds of thermometers: clinical thermometers and laboratory thermometers.

🎯 Exam Tip: Always specify the two main types and their primary uses when asked, as this shows a basic understanding.

 

Question 3. How can we convert the temperature of Celsius scale to Kelvin scale?
Answer: We can easily convert a temperature from the Celsius scale to the Kelvin scale by adding 273.15 to the Celsius temperature.
\( \text{Temperature in Kelvin scale} = \text{Temperature in Celsius scale} + 273.15 \)
The Kelvin scale is an absolute temperature scale, meaning 0 Kelvin is absolute zero, where all molecular motion stops.
In simple words: To change Celsius to Kelvin, you just add 273.15 to the Celsius number.

🎯 Exam Tip: Remember the conversion constant 273.15; it's a common point of error if misremembered or rounded incorrectly.

 

Question 4. Can a clinical thermometer be used to measure the temperature of boiling water or ice?
Answer: No, a clinical thermometer cannot be used to measure the temperature of boiling water or ice. Its temperature range is typically from 35 °C to 42 °C, which is too narrow for boiling water (100 °C) or ice (0 °C). Attempting to measure these temperatures could damage the thermometer. Therefore, a laboratory thermometer, with its wider range, would be needed.
In simple words: No, you cannot use a clinical thermometer for boiling water or ice. Its range is too small, and it could break.

🎯 Exam Tip: Always be aware of the specific temperature range for which each type of thermometer is designed.

 

Question 6. Which substance is used for measuring temperature in a laboratory thermometer?
Answer: The substance commonly used for measuring temperature in laboratory thermometers is alcohol or mercury. Alcohol is often colored red to make it easier to see the reading against the glass tube. Both liquids expand and contract predictably with temperature changes.
In simple words: Laboratory thermometers usually use alcohol (often colored) or mercury to show the temperature.

🎯 Exam Tip: Be able to name common liquids used in thermometers and explain why they are suitable (e.g., expand/contract uniformly).

 

Question 7. Mark the zero value for a normal laboratory thermometer-
(i) What is the minimum temperature it can measure?
(ii) What is the maximum temperature it can measure?
(iii) What is the minimum temperature that can be read?
Answer:
(i) A normal laboratory thermometer can typically measure a minimum temperature of -10 °C.
(ii) The maximum temperature it can measure is usually 110 °C.
(iii) The smallest temperature value that can be accurately read (its least count) is often 1.0 °C, meaning it can read in full degree increments.
In simple words: A regular lab thermometer can measure from -10°C to 110°C, and its smallest reading step is 1.0°C.

🎯 Exam Tip: Understand the concept of 'least count' of a measuring instrument, which is the smallest value it can measure accurately.

 

Question. What is called a 'room thermometer'?
Answer: A 'room thermometer' is a type of thermometer specifically designed to tell us the approximate temperature of a room or a place. These thermometers provide a general idea of the ambient temperature, helping us know how hot or cold our surroundings are. They are often less precise than laboratory thermometers.
In simple words: A room thermometer is a simple tool that shows how hot or cold a room is.

🎯 Exam Tip: Differentiate room thermometers from clinical or laboratory thermometers based on their typical function and precision.

 

Question 9. Which is the temperature scale commonly used in clinical thermometers? Also tell its unit.
Answer: The temperature scale commonly used in clinical thermometers is the Celsius scale. The unit of temperature on this scale is called degree Celsius, which is represented by the symbol °C. Many clinical thermometers also have a Fahrenheit scale for convenience.
In simple words: Clinical thermometers mainly use the Celsius scale, and its unit is degree Celsius (°C).

🎯 Exam Tip: Clinical thermometers often display both Celsius and Fahrenheit scales, but Celsius is the standard in many parts of the world.

 

Question 11. Tell the temperature range of clinical thermometer on Fahrenheit scale.
Answer: The temperature range of a clinical thermometer on the Fahrenheit scale is typically from 94 °F to 108 °F. This range covers the usual and fever temperatures of the human body. It is designed specifically for human body temperature measurement.
In simple words: On the Fahrenheit scale, a clinical thermometer can measure from 94°F to 108°F.

🎯 Exam Tip: Remember the Fahrenheit range of a clinical thermometer (94°F to 108°F) in addition to the Celsius range (35°C to 42°C).

 

Question 12. During the COVID-19 pandemic, some special thermometers were used, which could measure the temperature of a person from a distance. What were those?
Answer: During the COVID-19 pandemic, non-contact thermometers, also known as infrared thermometers, were widely used. These devices could measure a person's temperature without physical contact. This helped reduce the risk of spreading the disease, as there was no direct touch between the person being screened and the thermometer user.
In simple words: During COVID-19, special non-contact thermometers, called infrared thermometers, were used to check temperature from afar.

🎯 Exam Tip: Understand the practical application of different thermometer types, especially in health and safety contexts.

 

Question 13. On what factors does the body temperature of a person depend?
Answer: The body temperature of a person depends on several factors, including their age, the time of day, and their activity level. For instance, children often have slightly higher temperatures, body temperature can fluctuate throughout the day, and physical exercise can temporarily raise it. Illness also significantly impacts body temperature.
In simple words: A person's body temperature changes based on how old they are, what time it is, and if they have been active.

🎯 Exam Tip: When discussing factors affecting body temperature, consider biological (age, metabolism) and environmental (activity, time of day) influences.

 

Question 14. What is the normal temperature range of the human body?
Answer: The normal temperature range of the human body generally does not go below 35 °C and does not rise above 42 °C. Maintaining this narrow range is crucial for the body's proper functioning, and significant deviations often indicate a health issue.
In simple words: A human body's normal temperature usually stays between 35°C and 42°C.

🎯 Exam Tip: Memorize the normal human body temperature range in Celsius (35°C to 42°C) as it defines healthy physiological limits.

 

Question 15. Why do the maximum and minimum air temperatures of a particular place keep changing every day?
Answer: The maximum and minimum air temperatures of a specific place change daily because the weather depends on many factors. These factors include the amount of sunlight received, cloud cover, wind patterns, humidity, and atmospheric pressure, all of which vary from day to day and season to season. The earth's rotation also causes daily cycles of heating and cooling.
In simple words: The highest and lowest temperatures each day change because of many weather factors like sun, clouds, and wind, which are always shifting.

🎯 Exam Tip: Connect daily temperature variations to broader meteorological factors like solar radiation, cloud cover, and air currents.

 

Question 16. What is called 'absolute zero temperature'?
Answer: Absolute zero temperature is defined as -273.15 °C. On the Kelvin scale, this is represented as 0 Kelvin. It is the theoretical lowest possible temperature where particles have the minimum possible kinetic energy, meaning all atomic motion effectively ceases. Scientists have come very close to this temperature in laboratories.
In simple words: Absolute zero temperature is the coldest possible temperature, which is -273.15°C or 0 Kelvin. At this point, everything stops moving.

🎯 Exam Tip: Remember both the Celsius equivalent (-273.15 °C) and the Kelvin definition (0 K) for absolute zero, and understand its physical meaning.

 

Short Answer Type Questions

 

Question 1. Why can't the temperature of every person be 37°C?
Answer: The temperature of every person is not exactly 37.0 \(^{\circ}\text{C}\). The term "normal temperature" is actually an average that comes from measuring many healthy people. This means that a perfectly healthy person might have a slightly different temperature than 37.0 \(^{\circ}\text{C}\). The average helps us understand typical body function, but individual variations are common.
In simple words: Not everyone has a body temperature of exactly 37.0 \(^{\circ}\text{C}\). That number is an average, so healthy people can have temperatures a little higher or lower.

🎯 Exam Tip: When discussing body temperature, always clarify that 37°C is an average and healthy individuals can naturally have temperatures slightly varying from this mean.

 

Question 2. How was fever detected before the invention of thermometer?
Answer: Before thermometers were invented, people checked for fever by feeling a person's pulse. In older times, especially in India, it was known that fever would change the pulse rate. However, checking only the pulse was not always accurate because other things can also make a person's pulse change. A faster pulse is often a sign the body is working harder to fight off sickness, but it isn't a precise measure for fever.
In simple words: People used to feel a person's pulse to guess if they had a fever. They knew fever changed the pulse, but this method was not always exact.

🎯 Exam Tip: For historical questions, explain the traditional method and also highlight its limitations compared to modern, precise tools like thermometers.

 

Question 3. What precautions should be taken while using a laboratory thermometer?
Answer: When using a laboratory thermometer, you need to be very careful:
1. Handle it gently. If the thermometer hits something hard, it can easily break.
2. Do not hold it by the bulb part at the bottom. The bulb is very delicate and can affect the reading if touched. Always hold it by the top stem.
In simple words: Always handle a laboratory thermometer carefully. Do not drop it or touch the glass bulb at the end.

🎯 Exam Tip: Remember to emphasize both physical care (avoiding breakage) and proper handling technique (not touching the bulb) for accurate and safe use of laboratory thermometers.

 

Question 5. Who is 'Anna Mani'? Explain his contribution.
Answer: Anna Mani (1918-2001) was an Indian scientist who was widely known as the 'Weather Woman of India'. She was responsible for inventing and building a large number of weather measurement instruments. Her work helped reduce India's need to rely on other nations for these important tools. She also explored how India could use wind and solar energy. Her contributions helped India become a global leader in renewable energy.
In simple words: Anna Mani was an Indian scientist called the 'Weather Woman of India'. She made many weather tools and helped India use wind and solar power.

🎯 Exam Tip: When describing a scientist's contribution, mention their key field, specific achievements (e.g., inventions, research areas), and the impact of their work.

 

Question 6. What is the maximum and minimum possible temperature?
Answer: There is no known limit to the highest temperature that can exist; it can theoretically go infinitely high. However, based on scientific understanding, there is a definite limit to the lowest temperature that can be achieved. This lowest possible temperature is very close to -273.15 \(^{\circ}\text{C}\), which is also known as 0 Kelvin. This point is called absolute zero temperature.
In simple words: There is no highest temperature, but there is a coldest possible temperature called absolute zero, which is -273.15 \(^{\circ}\text{C}\) or 0 Kelvin.

🎯 Exam Tip: Clearly state that there's no upper limit for temperature but a definite lower limit (absolute zero), remembering to mention its value in both Celsius and Kelvin.

 

Question 7. Which is better among mercury thermometer and digital thermometer and why?
Answer: Digital thermometers are generally considered better than mercury thermometers. Mercury is a highly toxic substance, which means it is poisonous. If a mercury thermometer breaks by accident, it is very difficult to clean up the mercury safely and dispose of it properly. Digital thermometers do not use mercury, so they are much safer. Additionally, their display shows the temperature as clear numbers, making them easier to read.
In simple words: Digital thermometers are better because they don't use poisonous mercury and are easier to read than mercury thermometers.

🎯 Exam Tip: When comparing, focus on safety (mercury's toxicity) and ease of use (digital display) as the main advantages of digital thermometers over mercury ones.

 

Long Answer Type Questions

 

Question 1. Which precautions should be taken while using a digital clinical thermometer?
Answer: When using a digital clinical thermometer, you should follow these important precautions to ensure accurate readings and hygiene:
1. Always wash your hands and clean the tip of the digital thermometer with soap and water before and after use.
2. Reset the thermometer by pressing the reset button to clear any previous readings.
3. Place the thermometer carefully under the tongue and keep your mouth closed until the reading is complete.
4. Wait for the thermometer to signal that it's ready, usually by making a beeping sound or flashing a light.
5. Take the thermometer out from your mouth and read the temperature displayed on the digital screen.
6. After each use, clean the tip again with soap and water and dry it properly before storing it. These steps help prevent the spread of germs and ensure the thermometer works correctly.
In simple words: To use a digital clinical thermometer safely and correctly, always wash your hands and the thermometer tip, reset it, place it properly in your mouth, wait for the beep, read the display, and then clean it again.

🎯 Exam Tip: Clearly list the precautions for using a digital clinical thermometer, covering hygiene, correct operation, and proper cleaning for both accuracy and safety.

 

Question 2. Which are the most commonly used temperature scales and also tell their units?
Answer: The three most commonly used temperature scales are:
1. **Celsius scale:** This scale is widely used in clinical thermometers for measuring temperature. The unit of temperature on this scale is called degree Celsius, which is represented by \(^{\circ}\text{C}\).
2. **Fahrenheit Scale:** Digital thermometers often use the Fahrenheit scale. The unit of temperature on this scale is called degree Fahrenheit and it is represented by \(^{\circ}\text{F}\).
3. **Kelvin Scale:** Scientists frequently use the Kelvin scale for scientific work. The unit of temperature on this scale is Kelvin, which is represented by K. It is important to note that Kelvin is also the SI unit of temperature. Each scale uses different reference points for freezing and boiling, leading to distinct numerical values for the same temperature.
In simple words: The three main temperature scales are Celsius (\(^{\circ}\text{C}\)), Fahrenheit (\(^{\circ}\text{F}\)), and Kelvin (K). Kelvin is the standard scientific unit.

🎯 Exam Tip: Remember to list all three major scales (Celsius, Fahrenheit, Kelvin) and their correct units, noting that Kelvin is the SI unit and does not use the degree symbol.

 

Question 3. How are the units of different scales of temperature written? Explain.
Answer: When writing temperature scales and their units, follow these specific rules:
1. The full names of temperature scales, such as Celsius, Fahrenheit, and Kelvin, always begin with a capital letter.
2. For the units of temperature, the word "degree" in "degree Celsius" and "degree Fahrenheit" starts with a lowercase letter, while the words "Celsius" and "Fahrenheit" themselves are capitalized. The unit "kelvin" (k) starts with a lowercase letter.
3. The symbols for all units (\(^{\circ}\text{C}\), \(^{\circ}\text{F}\), K) are always capital letters. It is important to remember that the degree sign (\(^{\circ}\)) is not used with Kelvin.
4. When writing a temperature value, always leave a space between the number and its unit (e.g., 25 \(^{\circ}\text{C}\)). If you write the unit in its full form, use the plural "degrees" for values greater than one (e.g., "ten degrees Celsius"). These rules ensure clear and correct scientific communication.
In simple words: Scale names (Celsius, Fahrenheit, Kelvin) start with capitals. Units like "degree Celsius" have "degree" in lowercase, but "Celsius" is uppercase. Kelvin's symbol is K (capital), without a degree sign. Always put a space between the number and its unit.

🎯 Exam Tip: Pay close attention to capitalization (e.g., Celsius vs. celsius), the correct use of the degree symbol (only with Celsius and Fahrenheit), and proper spacing between the number and the unit for accurate scientific notation.

 

Question 4. Explain digital clinical thermometer with a diagram?
Answer: A digital clinical thermometer is a device primarily used for measuring a person's body temperature. These thermometers are designed to show temperature readings digitally on a small screen, making them very easy to read and understand. They operate using batteries and are also known simply as digital thermometers. Their digital display provides a quick and accurate reading, which is why they are widely used for health monitoring at home.
In simple words: A digital clinical thermometer measures body temperature and shows the result as numbers on a screen. It runs on batteries and is easy to read.

🎯 Exam Tip: Focus on the key features: measures body temperature, shows reading digitally, is battery-powered, and is easy to read, especially when explaining its function.

 

Question 5. Explain the structure of laboratory thermometer by drawing a diagram.
Answer: A laboratory thermometer consists of a long, narrow, and uniformly thick glass tube that is sealed at both ends. At one end of this tube, there is a small bulb which contains a liquid, typically alcohol (often colored red to make it more visible) or mercury. Above the bulb, within the tube, a very fine column of this liquid can be observed. The tube also features a Celsius scale marked along its length. When the temperature changes, the liquid in the column expands or contracts, causing its level to rise or fall. The point where the top of the liquid column aligns with the Celsius scale indicates the temperature reading. This design allows for precise measurements in various laboratory settings.
In simple words: A laboratory thermometer is a sealed glass tube with a bulb of liquid (like alcohol or mercury) at one end. A thin line of liquid moves along a Celsius scale, showing the temperature.

🎯 Exam Tip: Describe the key parts: long glass tube, bulb with liquid (alcohol/mercury), narrow liquid column, and a marked scale (Celsius) for reading temperature changes. Highlight how the liquid expands or contracts to indicate temperature.

 

Question 6. Explain the method of using digital clinical thermometer.
Answer: To measure your body temperature using a digital clinical thermometer, follow these simple steps:
1. Start by washing your hands and cleaning the tip of the digital thermometer with soap and water to ensure hygiene.
2. Next, reset the thermometer by pressing its reset button to clear any previous temperature readings.
3. Carefully place the thermometer under your tongue and keep your mouth closed until it finishes measuring.
4. Wait for a clear signal that the reading is complete, which is usually a beeping sound or a flashing light.
5. Take the thermometer out from your mouth and read the temperature displayed on its digital screen.
6. After use, clean the tip of the thermometer again with soap and water and dry it properly before putting it away. Following these steps helps ensure you get an accurate and hygienic temperature reading.
In simple words: To use a digital thermometer, first wash your hands and the tip. Then reset it, place it under your tongue, wait for the beep, read the temperature, and clean it again.

🎯 Exam Tip: Clearly list the sequential steps for using the thermometer, from hygiene and resetting to placement, reading, and post-use cleaning, to demonstrate a full understanding of the method.

 

Question 7. Show the equipment arranged for measuring the room temperature and water by diagram.
Answer: This answer would typically involve a diagram showing two separate setups: one illustrating a thermometer placed in a room to measure air temperature, and another showing a thermometer immersed in a beaker of water to measure water temperature. Both thermometers should be correctly positioned, with their bulbs fully in the medium being measured and readings taken at eye level. The diagram should label the components clearly, such as the thermometers, beaker, water, and the surrounding environment.
In simple words: This answer would be a drawing that shows one thermometer in a room to measure the air and another thermometer in a cup of water to measure the water, both labeled correctly.

🎯 Exam Tip: For diagram-based questions, ensure your drawing clearly labels all components and accurately depicts the setup for temperature measurement, including the correct placement of thermometers in both air and liquid.

 

Question 8. Compare clinical thermometer and laboratory thermometer?
Answer: Clinical thermometers and laboratory thermometers share some basic similarities, but they also have distinct differences in their design and use.
**Similarities:**
1. Both types of thermometers are made from a long, thin glass tube with a closed end.
2. Each contains a narrow column in the middle and a bulb at one end, which is usually filled with mercury.
3. Both thermometers typically have the Celsius scale marked on them, allowing for temperature measurement.
**Differences:**
1. **Temperature Range:** A clinical thermometer has a limited temperature range, typically from 35\(^{\circ}\text{C}\) to 42\(^{\circ}\text{C}\), which is suitable for measuring human body temperature. In contrast, a laboratory thermometer has a much wider temperature range, usually from -10\(^{\circ}\text{C}\) to 110\(^{\circ}\text{C}\), making it suitable for various experimental measurements.
2. **Purpose:** Clinical thermometers are specifically designed to measure human body temperature. Laboratory thermometers, on the other hand, are used to measure the temperature of different objects and liquids in a laboratory setting. The wider range and lack of a kink in a laboratory thermometer make it more versatile for scientific experiments.
In simple words: Both are glass tubes with mercury and a scale. But clinical thermometers measure body temperature (35-42\(^{\circ}\text{C}\)), while laboratory thermometers measure other things (widely, -10-110\(^{\circ}\text{C}\)).

🎯 Exam Tip: When comparing, always discuss both similarities and differences. Key points for comparison include their temperature ranges, specific uses, and the presence or absence of a kink (though not mentioned in source, it's a key differentiator).

 

Question 2. What are thermometers? Explain the different commonly used thermometers.
Answer: A thermometer is a scientific instrument specifically designed to measure temperature. There are several types of thermometers, each used for different purposes:
1. **Clinical Thermometer:** This type is mainly used to measure the temperature of the human body. It has a very small measuring range, typically from 35\(^{\circ}\text{C}\) to 42\(^{\circ}\text{C}\), and usually has a kink to prevent mercury from falling back quickly.
2. **Laboratory Thermometer:** Used in scientific laboratories, these thermometers measure the temperature of various objects and liquids. They have a wider temperature range, typically from -10\(^{\circ}\text{C}\) to 110\(^{\circ}\text{C}\).
3. **Digital Thermometer:** These modern thermometers display the temperature as clear numbers on a screen. They are often used as clinical thermometers because they are easy to read and do not contain mercury.
4. **Infrared Thermometer:** Also known as non-contact thermometers, these devices measure temperature from a distance without needing to touch the object or person. They became very common for quick temperature checks during the COVID-19 pandemic.
5. **Room Thermometer:** These are used to give an approximate idea of the air temperature inside a room or a specific environment. Each type of thermometer is designed with specific features to best suit its intended use.
In simple words: Thermometers measure temperature. Common types are clinical (for body), laboratory (for experiments), digital (easy-to-read numbers), infrared (non-contact), and room thermometers (for air temperature).

🎯 Exam Tip: When explaining thermometers, define what they do and then clearly describe at least three different types, mentioning their specific uses or key features for full marks.

RBSE Class 6 Science Chapter 7 Notes

Temperature and Its Measurement Class 6 Notes

• 1. The temperature of a body tells us how hot or cold it is.
• 2. The instrument which measures temperature is called a thermometer.
• 3. Generally two types of thermometers are used to measure temperature - clinical thermometer and laboratory thermometer.
• 4. A clinical thermometer is used for measuring body temperature.
• 5. Normal temperature of a healthy adult is taken to be 37.0 \(^{\circ}\text{C}\) or 98.6 \(^{\circ}\text{F}\).
• 6. Laboratory thermometers typically have a temperature range from -10 \(^{\circ}\text{C}\) to 110 \(^{\circ}\text{C}\).
• 7. The three most-used scales of temperature are: (a) the Celsius scale, (b) the Fahrenheit scale, and (c) the Kelvin scale. The units of temperature in these scales are (a) degree Celsius, denoted by \(^{\circ}\text{C}\), (b) degree Fahrenheit, denoted by \(^{\circ}\text{F}\), and (c) kelvin, denoted by K.
• 8. Room thermometer-These give an approximate idea of the room temperature.
• 9. Air temperature is an important weather parameter and is monitored at weather stations all over the world.