Selina Concise Solutions for ICSE Class 7 Geography Chapter 2 Scale and Distance

THINK AND ANSWER

Question: Why do you think that the knowledge of scale is important for reading a map ?
Answer:
The two cities in the space of an inch will be found on a map where the scale is used. e.g. 1 cm on map = 100 km on ground. Scales are important as without scales distance between places can’t be judged.
Knowing the scale helps us understand the real-world size of the area shown on a flat piece of paper. It allows us to calculate how long it will take to travel from one point to another in real life.
Teacher's Tip: Think of the scale as a "shrinking machine" that keeps everything in the right proportion so the map looks like a small version of the real world.
Exam Tip: Always mention that scale is a ratio between map distance and ground distance to get full marks for the definition.

VALUES AND LIFE SKILLS

Question: Your friend has invited you to his house. He has drawn a rough sketch on a paper showing the direction to his house for you. How does the sketch help you ? What quality of your friend is shown through in this gesture ?
Answer:
Sketch will help to reach friend’s house easily and early. A friend is showing a genuine interest and is real. He actually wants a friend to visit his house.
A sketch provides a visual guide that simplifies complex directions into easy-to-follow landmarks. This thoughtful gesture shows that your friend is caring and values your time by making your journey stress-free.
Teacher's Tip: Remember that a sketch is different from a map because it is usually drawn without a specific scale.
Exam Tip: When answering value-based questions, connect the physical benefit (reaching easily) with the emotional quality (care and interest).

EXERCISES

A. Fill in the blanks. one has been done for u
Distance on the map | Distance on the ground | Scale
1. 5 cm | 25 km | 1 cm = 5 km
2. 10 cm | 100 km | 1 cm = 10 km
3. 2 cm | 60000 m | 1 cm = 30 km
4. 7 cm | 49 m | 1 cm = 7 m
5. 6 cm | 60,000 km | 1 cm = 10,000 km
To find the scale, you simply divide the distance on the ground by the distance on the map. This tells you exactly how much real-world distance is represented by just one unit on your paper.
Exam Tip: Double-check the units (km, m, cm) before writing your final scale answer to avoid silly mistakes.

B. Match the following
Column A | Column B
1. scale                        (i) Words
2. statement scale     (ii) Straight line divided into lengths
3. linear scale            (iii) Curved line
4. ruler                       (iv) Ratio
5. twine                      (v) Straight line
Answer:
1. Scale - (iv) Ratio
2. Statement scale - (i) Words
3. Linear scale - (ii) Straight line divided into lengths
4. Ruler - (v) Straight line
5. Twine - (iii) Curved line
Each tool or term relates to how we measure or describe distance on maps versus reality. For example, a twine is flexible, making it perfect for measuring things that aren't straight, like rivers.
Teacher's Tip: Match the "flexible" tool (twine) with the "curved" object and the "stiff" tool (ruler) with the "straight" object.
Exam Tip: Draw straight lines for matching or write the correct number next to the option to keep your answer sheet neat.

C. Choose the correct answer.

Question 1: This is the ratio of distance between two places on a map to the actual distance between the same two places on the ground.
1. scale
2. map
3. globe
4. atlas
Answer: 1. scale
The scale acts as the mathematical link that shrinks the huge world down to fit on a piece of paper. It ensures that the relative distances between all features on the map remain accurate.
Teacher's Tip: Think of "Ratio" as the keyword for "Scale".
Exam Tip: Read all options before choosing, even if the first one seems correct, to ensure you haven't missed a better term.

Question 2: This scale is stated in words:
1. Verbal
2. Statement
3. Both of these
4. None of these
Answer: 3. Both of these
Verbal and Statement scales are two names for the same thing, where the scale is explained using a simple sentence. For example, saying "one centimeter represents ten kilometers" is both a verbal and a statement scale.
Teacher's Tip: "Verbal" comes from the word for speaking, and "Statement" is something you say or write in words.
Exam Tip: In multiple-choice questions, "Both of these" is often the correct answer if two terms are synonyms.

Question 3: The distance between two points along a straight line can be measured by this method
1. Twine
2. Ruler
3. Compass
4. Stick
Answer: 2. Ruler
A ruler is a rigid tool designed specifically for measuring direct, straight paths between two points. It provides an immediate numerical measurement in units like centimeters or inches.
Teacher's Tip: Only use a ruler for straight lines; it won't work for winding roads or rivers!
Exam Tip: When the question specifies "straight line," the answer will almost always involve a ruler.

Question 4: In this fraction, the numerator is always 1.
1. Representative Fraction
2. Refractive Fraction
3. Reduction Fraction
4. Reorganization Fraction
Answer: 1. Representative Fraction
A Representative Fraction (R.F.) is a way of showing scale where the first number (numerator) is 1, representing the map distance. The second number (denominator) shows how many units of that same size exist on the actual ground.
Teacher's Tip: R.F. is unique because it doesn't use specific units like "cm" or "km" in the final fraction.
Exam Tip: Remember that in R.F., the numerator and denominator must always be converted to the same unit of measurement.

D. State whether the following are true or false.

Question 1: Verbal scale is stated in words.
Answer: True.
A verbal scale uses language to explain the relationship between map and ground distances. It is the easiest type of scale for most people to understand quickly.
Teacher's Tip: "Verbal" means using words, just like a verbal test.
Exam Tip: If a statement matches the basic definition of a term, it is almost certainly true.

Question 2: A statement scale consists of a straight line which is divided into lengths.
Answer: False.
Correct : A linear consists of a straight line which is divided into lengths.
A statement scale uses words, while a linear scale uses a physical drawn line to show distances. They are two distinct methods of representing map scales.
Teacher's Tip: Linear = Line. Associate the word with the visual representation.
Exam Tip: When correcting a false statement, always replace the incorrect term with the correct one to show full understanding.

Question 3: The numerator in a Representative Fraction expresses the actual distance between two places on the ground.
Answer: False.
Correct : The denominator in a Representative Fraction expresses the actual distance between two places on the ground.
In a fraction, the top number (numerator) represents the small map distance, usually 1. The bottom number (denominator) represents the much larger real-world distance.
Teacher's Tip: Remember: Numerator = Map (Small), Denominator = Distance on Ground (Big).
Exam Tip: For R.F. questions, always remember the order is Map Distance over Ground Distance.

Question 4: The distance along a curved line is measured by a ruler.
Answer: False.
Correct : The Distance along a curved line is measured by a divider.
Since a ruler cannot bend, it is impossible to accurately measure a curve with one. A divider or a piece of twine can follow the twists and turns of a feature like a river or coastline.
Teacher's Tip: Think of trying to measure a circle with a stiff wooden ruler; it just doesn't work!
Exam Tip: In geography, remember that "curved" features require "flexible" or "stepped" measurement tools.

E. Answer the following questions briefly

Question 1: What is meant by the scale of a map ?
Answer:
A scale is the ratio of the distance between two places on the map to the actual distance between the same two places on the ground.
This ratio helps us compress massive geographical areas into a size that we can easily study. Without it, a map would just be a drawing without any real-world meaning.
Teacher's Tip: Use the word "ratio" to sound like a geography expert.
Exam Tip: Drawing a small diagram showing "1cm on map -> 1km on ground" can help illustrate your answer.

Question 2: Which three ways are used to represent the scale of a map?
Answer:
The three ways used to represent the scale of a map are :
(a) Verbal or statement scale - The scale is stated in words. The units are usually mentioned in this type of scale, for example, 1 cm = 10 km or 1 cm to 10 km. It means that 1 cm on the map is equal to 10 km on the ground.
(b) Graphical or linear scale - This consists of a straight line which is divided into lengths that represent given distances on the earth’s surface.
(c) Representative fraction (RF) - This is a fraction in which the numerator expresses the distance on the map and the denominator represents the actual distance on the ground. It must be noted that the numerator is always 1 and both the numerator and the denominator are expressed in the same unit.
Each of these three methods serves a different purpose, with the graphical scale being very useful if the map is resized. The R.F. is used internationally because it doesn't depend on specific units like miles or kilometers.
Teacher's Tip: Remember the "Big Three": Words (Verbal), Lines (Linear), and Fractions (R.F.).
Exam Tip: List all three methods and provide a very short example for each to secure full marks.

Question 3: Convert the statement scale 1 cm = 100 km into R.F. scale.
Answer:
R.F. = Distance on map/Distance on ground = 1 cm100 km
= 1 cm10,000,000 cm = 1 : 10,000,000
[because 1 km = 1000 m and 1 m = 100 cm]
therefore 100 km = 100 x 1000 x 100 = 10,000,000 cm
To convert a scale, you must make sure both numbers are in centimeters before you put them into the fraction. Once they are in the same unit, you remove the "cm" labels to create a pure ratio.
Teacher's Tip: Multiply by 100,000 to convert kilometers directly to centimeters.
Exam Tip: Always show your calculation steps and the units conversion to avoid losing partial marks.

Question 4: What method would you use to measure the length of a river ?
Answer:
The rivers are curved. To measure length of rivers we use either the divider method or the twine methods.
These methods allow you to follow every bend and loop of a winding river accurately. Once you have the measurement of the twine or the number of divider steps, you compare it against the map's linear scale.
Teacher's Tip: Think of a piece of string (twine) as a flexible ruler that can follow any shape.
Exam Tip: Mention that rivers are "curved" to explain why a standard ruler cannot be used directly.

F. Answer the following questions in detail.

Question 1: Describe any two ways of representing a map scale.
Answer:
The map scale can be represented as :
(a) Verbal or statement scale - The scale is stated in words. The units are usually mentioned in this type of scale, for example, 1 cm= 10 km or 1 cm to 10 km. It means that 1 cm on the map is equal to 10 km on the ground.
(b) Graphical or linear scale - This consists of a straight line which is divided into lengths that represent given distances on the earth’s surface.
A statement scale is perfect for a quick, general understanding of the map's size. A linear scale is more technical and remains accurate even if the map image is enlarged or shrunk.
Teacher's Tip: Use the statement scale for talking about maps, and the linear scale for measuring things on the map.
Exam Tip: Detailed answers should define the term and provide an example or descriptive sentence to be complete.

Question 2: Describe the method by which the distance on a curved line is measured.
Answer:
The distance on a curved line is measured using a piece of twine or a divider.
In divider method, a divider whose pointed ends are 1 or 2 cm apart is used. Beginning at one end of the feature to be measured, the divider is turned continuously till the other end is reached. The number of turns are counted and then using the scale of the map, the actual distance on the ground calculated.
In the twine method, a twine is placed along the feature to be measured from one end to other. The length of the twine is then measured in cm or inches using a ruler or linear scale and then converted into km or miles using the scale of the given map.
Using a divider is like taking small "steps" along the curve, while the twine method is like laying a flexible path. Both methods eventually require you to use a ruler and the map's scale to get the final real-world distance.
Teacher's Tip: For the divider method, remember that Distance = (Number of turns × divider width) × Scale.
Exam Tip: Describe both the divider and twine methods if the question asks for a general description of measuring curved lines.

Question 3: How is distance on a map measured by a piece of twine?
Answer:
Take the piece of the twine, make a knot at one end and place the knotted end on the starting point of the distance to .be measured. Now move the twine along the object to be measured by slowly placing the twine bit by bit along the route following each bend or curve as closely as possible. When you reach the end of the route you are measuring, mark that end with ink. Now place the twine on the scale with the knotted end at 0 and see how far the ink-marked end reaches on the scale. Measure the length and convert into kilometres. If the distance to be measured is longer than the printed scale on the map, place the twine on the ruler in the same way, calculate the number of centimetres it covers and convert that into kilometres.
This method is highly effective because twine can mimic any irregular shape perfectly. The final step of comparing the marked twine to a ruler is crucial for turning the physical length into a useful map distance.
Teacher's Tip: Using a knot at the start and ink at the end ensures you don't lose your measurement points while moving the twine.
Exam Tip: Explain the process step-by-step: knotting, tracing, marking, and finally measuring against a scale or ruler.

G Picture study
Look at the picture and answer the questions
[Image showing a linear scale with markings: km 50 25 0 50 100 150 200 km]

Question 1: What type of scale is shown alongside ?
Answer:
A graphic scale or linear scale.
This visual bar helps map readers measure distances directly without needing complex math. It acts like a mini-ruler built specifically for that particular map.
Teacher's Tip: Graphical and Linear are two names for the same thing; you can use either!
Exam Tip: Look for the "bar" shape; if you see a bar with numbers, it’s a linear scale.

Question 2: State a feature of this scale.
Answer:
This consists of a straight line which is divided into lengths that represent given distances on the earth’s surface. It is usually drawn near the lower portion of the map.
The scale is often split into primary and secondary divisions to allow for both large and very precise measurements. It stays accurate even if the map is photocopied and its physical size changes.
Teacher's Tip: The part to the left of '0' is for small, precise measurements, and the part to the right is for larger distances.
Exam Tip: Mentioning its location (bottom of the map) is a great "feature" to include in your answer.

LET’S DO SOMETHING

Question: Look at the plan of a school given here and note the scale given at the top of the plan : 1 cm to 8 m. This verbal scale means that 1 cm on the paper represents 8 m on the ground. Use this scale to find out the length and breadth of the different places shown in the plan.
Answer:The length and breadth of different places is as follows:
(a) Playground
Length of the playground = 3.5 cm = 3.5 × 8 m = 27 m (Correction: 3.5 × 8 = 28 m)
Breadth of the playground = 4 cm = 4 × 8 m = 32 m

(b) Office
Length of the office = 1.1 cm = 1.1 × 8 m = 8.8 m
Breadth of the office = 0.8 cm = 0.8 × 8 m = 6.4 m
(c) Library
Length of the library = 1.1 cm = 1.1 × 8 m = 8.8 m
Breadth of the library = 0.8 cm = 0.8 × 8 m = 6.4 m

(d) Classroom
Length of the Classroom = 4.35 cm = 4.35 × 8 m = 34.8 m
Breadth of the Classroom = 2.1 cm = 2.1 × 8 m = 16.8 m (Correction: 2.1 × 8 = 16.8, OCR says 16.2)

(e) Tennis Court
Length of the Tennis Court = 1.7 cm = 1.7 × 8 m = 13.6 m
Breadth of the Tennis Court = 2.7 cm = 2.7 × 8 m = 21.6 m

(f) Gym
Length of the Gym = 1.5 cm = 1.5 × 8 m = 12 m
Breadth of the Gym = 1.7 cm = 1.7 × 8 m = 13.6 m

(g) Canteen
Length of the Canteen = 1.5 cm = 1.5 × 8 m = 12 m
Breadth of the Canteen = 1.75 cm = 1.75 × 8 m = 14 m
To find these real-life sizes, you measure the drawing with your ruler and then multiply that number by 8. This is how architects and builders use blueprints to know exactly how big to build a room.
Teacher's Tip: Keep a ruler handy whenever you are looking at a "plan" or a "blueprint" to understand the real size.
Exam Tip: When doing calculations like these, always include the multiplication step (cm × 8) to show how you got your answer.