ICSE Class 6 Physics Sample Paper with Solutions Set 03

ICSE Board
Class VI Physics
Sample Paper - 3

Time: 2 Hours    Total Marks: 75

Question 1

Choose the correct answer out of the four available choices given under each question. [15 Marks]

1. Mechanical advantage (M.A), load (L) and effort (E) are related as [1 Mark]
(a) M.A = L × E
(b) M.A × E = L
(c) M.A × L = E
(d) None of the above

Answer: (b) M.A × E = L

Mechanical advantage is defined as the ratio of load to effort, hence M.A = L / E, which rearranges to M.A × E = L.

Teacher's Note:
a) Remember the basic definition and formula for simple machines where Load equals Effort multiplied by Mechanical Advantage.
b) Students often confuse the numerator and denominator in the ratio of load to effort.

2. Which of the following is not a lever of class II? [1 Mark]
(a) Nail cutter
(b) Scissors
(c) A bottle opener
(d) Wheel barrow

Answer: (b) Scissors

Scissors is a class I lever because the fulcrum is located between the load and the effort.

Teacher's Note:
a) Class I levers have the fulcrum in the middle, whereas Class II levers have the load between the fulcrum and effort.
b) Verify the positions of fulcrum, load, and effort for common household tools.

3. If the area of contact increases, then [1 Mark]
(a) Pressure decreases
(b) Pressure increases
(c) Pressure remains constant
(d) None of the above

Answer: (a) Pressure decreases

Pressure is inversely proportional to the area of contact for a constant force, so increasing area decreases pressure.

Teacher's Note:
a) Use the formula Pressure = Force / Area to explain inverse proportionality.
b) Do not confuse force with pressure; a larger area distributes the same force, resulting in lower pressure.

4. A force which always tends to slow down the motion of an object on a surface is [1 Mark]
(a) Weight
(b) Inertia
(c) Gravity
(d) Friction

Answer: (d) Friction

Frictional force acts in the direction opposite to the motion of an object, opposing and slowing it down.

Teacher's Note:
a) Friction is a contact force that arises when two surfaces move relative to each other.
b) Ensure students understand that friction always opposes relative motion.

5. Why is it harder to slide a stationary heavy box across the floor than to keep it sliding? [1 Mark]
(a) Sliding friction is greater than the static friction.
(b) Sliding friction is less than rolling friction.
(c) Static friction is greater than sliding friction.
(d) Sliding friction is more than rolling friction.

Answer: (c) Static friction is greater than sliding friction.

Static friction acts on stationary objects and is generally greater than sliding friction, requiring a larger initial force to start motion.

Teacher's Note:
a) Interlocking of irregularities between stationary surfaces causes higher static friction.
b) Watch out for option (a) which states the reverse relationship incorrectly.

6. Which of the following is not a fundamental unit? [1 Mark]
(a) Cubic metre
(b) Kilogram
(c) Metre
(d) Kelvin

Answer: (a) Cubic metre

Cubic metre is a derived unit of volume, whereas kilogram, metre, and kelvin are fundamental units.

Teacher's Note:
a) Fundamental units are independent units defined in the SI system, such as metre, kilogram, and second.
b) Derived units are formed by combining fundamental units, like length cubed for volume.

7. Rubbing your palms together creates warmth due to: [1 Mark]
(a) Air in between the two palms
(b) Gravity
(c) Friction between the two palms
(d) All of the above

Answer: (c) Friction between the two palms

Frictional force between rubbing surfaces converts mechanical energy into thermal energy (heat).

Teacher's Note:
a) Friction generates heat whenever two rough surfaces rub against each other.
b) Emphasize the conversion of energy due to frictional resistance.

8. Two like magnetic poles: [1 Mark]
(a) Attract each other
(b) Repel each other
(c) Repel when close and attract when far from each other
(d) Attract when close and repel when far from each other

Answer: (b) Repel each other

Like magnetic poles (North-North or South-South) always repel each other.

Teacher's Note:
a) State the fundamental law of magnetism clearly: like poles repel, unlike poles attract.
b) Do not confuse magnetic poles with gravitational or electrical charges under special conditions.

9. The length having the largest magnitude out of the following options is [1 Mark]
(a) 5 cm
(b) 7 mm
(c) 4 km
(d) 6 m

Answer: (c) 4 km

Converting all values to millimeters: 5 cm = 50 mm, 7 mm = 7 mm, 4 km = 4,000,000 mm, and 6 m = 6,000 mm. Thus, 4 km is the largest.

Teacher's Note:
a) Always convert all quantities to the same unit before comparing magnitudes.
b) Remember that 1 kilometre equals 1,000 metres.

10. The magnetism acquired by a magnetic material when it is kept near (or in contact with) a magnet, is called [1 Mark]
(a) Temporary magnetism
(b) Induced magnetism
(c) Permanent magnetism
(d) Induction

Answer: (b) Induced magnetism

The temporary magnetic property acquired by a magnetic substance in the presence of a magnet is called induced magnetism.

Teacher's Note:
a) Induction is the process, while induced magnetism is the property acquired.
b) Note that soft iron acquires induced magnetism easily and loses it quickly.

11. Water stored at a height in a dam possesses [1 Mark]
(a) Chemical energy
(b) Kinetic energy
(c) Potential energy
(d) Electrical energy

Answer: (c) Potential energy

Water stored at an elevation possesses gravitational potential energy due to its position.

Teacher's Note:
a) Potential energy depends on the mass, acceleration due to gravity, and height above ground level.
b) When the water falls, potential energy converts into kinetic energy.

12. Which of the following is not a non-contact force? [1 Mark]
(a) Frictional force
(b) Gravitational force
(c) Electrostatic force
(d) Magnetic force

Answer: (a) Frictional force

Frictional force requires physical contact between two surfaces, making it a contact force, unlike the other three.

Teacher's Note:
a) Non-contact forces act across a distance without physical touch (gravitational, magnetic, electrostatic).
b) Contact forces require physical touch between interacting objects.

13. A block of weight 400 N is kept on the floor. The area of contact is 4 m². The pressure exerted by the box on the floor is [1 Mark]
(a) 200 Pa
(b) 400 Pa
(c) 300 Pa
(d) 100 Pa

Answer: (d) 100 Pa

Pressure = Force / Area = 400 N / 4 m² = 100 Pa.

Teacher's Note:
a) Apply the formula P = F / A directly using given values.
b) Ensure the unit is expressed correctly in Pascals (Pa).

14. Every object in this universe, whether small or large exerts a force on every other object. What is the name of this force? [1 Mark]
(a) Electrostatic force
(b) Gravitational force
(c) Magnetic force
(d) Nuclear force

Answer: (b) Gravitational force

Gravitational force is a universal attractive force existing between any two objects possessing mass in the universe.

Teacher's Note:
a) Newton's law of gravitation applies to all masses across the universe.
b) Do not confuse gravitational force with contact forces or magnetic forces.

15. Calculate the distance between a man and a box when the work done to move the box was 100 J with a force of 15 N. [1 Mark]
(a) 16.6 m
(b) 26.6 m
(c) 6 m
(d) 6.6 m

Answer: (d) 6.6 m

Work (W) = Force (F) × Distance (s). Distance s = W / F = 100 J / 15 N = 6.66 m, which rounds to 6.6 m.

Teacher's Note:
a) Rearrange the work formula W = Fs to solve for displacement s.
b) Check units carefully: Joules divided by Newtons gives metres.

Question 2

(A) Name the following. [5 Marks]

1. Fundamental unit of temperature. [1 Mark]

Answer: kelvin.

Teacher's Note:
a) Kelvin is the SI base unit of temperature.
b) Do not write degree symbol with kelvin.

2. Simplest machine. [1 Mark]

Answer: Lever.

Teacher's Note:
a) A lever is considered the simplest form of machine.
b) Other simple machines include pulleys, inclined planes, and wheels and axles.

3. A quantity which depends on other quantities. [1 Mark]

Answer: Derived quantity.

Teacher's Note:
a) Derived quantities are expressed in terms of fundamental quantities.
b) Examples include speed, area, and volume.

4. Time taken by the Earth to complete one rotation about its own axis. [1 Mark]

Answer: Mean solar day.

Teacher's Note:
a) One rotation takes approximately 24 hours.
b) Distinguish between rotation (day and night) and revolution (seasons/year).

5. Force of friction between a rolling object and surface. [1 Mark]

Answer: Rolling friction.

Teacher's Note:
a) Rolling friction is much smaller than sliding friction.
b) This principle is used in ball bearings and wheels.

(B) Fill in the blanks. [5 Marks]

1. Electricity produced from water is called __________. [1 Mark]

Answer: Hydro-electricity.

Teacher's Note:
a) Hydro-electricity is generated using the potential energy of stored water.
b) It is a renewable source of energy.

2. The normal temperature of the body is __________. [1 Mark]

Answer: 37 °C.

Teacher's Note:
a) Normal human body temperature is 37 °C or 98.6 °F.
b) Always include the unit when specifying temperature.

3. To increase pressure, area of contact is __________. [1 Mark]

Answer: Decreased.

Teacher's Note:
a) Pressure is inversely proportional to area.
b) Smaller area leads to higher pressure for the same force.

4. __________ is the surest test of magnetism. [1 Mark]

Answer: Repulsion.

Teacher's Note:
a) Attraction can occur between a magnet and an unmagnetized magnetic material.
b) Repulsion occurs only between two like magnetic poles, making it the surest test.

5. Force of gravity is always directed towards the __________ of the Earth. [1 Mark]

Answer: Centre.

Teacher's Note:
a) Gravity pulls objects towards the Earth's center.
b) This gives weight its downward vertical direction.

Question 3

(A) Match the following. [5 Marks]

Answer:
1. - e (Correction based on standard textbook matches: Volume - m³, matching item 1 to e)
Corrected pairs:
1. Volume - e. m³
2. Heater - a. Electrical to heat
3. Claw hammer - b. Class I lever
4. Speed - c. m/s
5. Photo voltaic cell - d. Light to electrical

Teacher's Note:
a) Match physical quantities, devices, and instruments correctly with their respective units or functions.
b) Claw hammer acts as a Class I lever with the fulcrum between effort and load.

(B) Correct the following sentences. [5 Marks]

1. An object can be measured with an accuracy of 0.01 mm with a vernier calliper. [1 Mark]

Answer: An object can be measured with an accuracy of 0.1 mm with a vernier calliper.

Teacher's Note:
a) The least count of a standard school vernier calliper is typically 0.1 mm or 0.01 cm.
b) Check least count definitions carefully.

2. A class II lever has fulcrum in the middle. [1 Mark]

Answer: A class II lever has load in the middle.

Teacher's Note:
a) Class I levers have the fulcrum in the middle.
b) Class II levers have the load between the fulcrum and effort.

3. Weight of an object is the force with which an object gets attracted towards the ground. [1 Mark]

Answer: Weight of an object is the force with which an object gets attracted towards the centre of the Earth.

Teacher's Note:
a) Gravitational force is directed towards the center of the Earth.
b) Precise phrasing is important in definitions.

4. Static friction is lesser than sliding friction and greater than rolling friction. [1 Mark]

Answer: Static friction is greater than sliding friction and rolling friction.

Teacher's Note:
a) Static friction is always higher than sliding friction.
b) Rolling friction is the least among the three.

5. In a solar cell, light energy is converted to heat energy. [1 Mark]

Answer: In a solar cell, light energy is converted to electric energy.

Teacher's Note:
a) Solar cells generate electricity directly from sunlight via photovoltaic action.
b) Do not confuse solar cells with solar water heaters which convert light to heat.

Question 4

(A) Answer the following. [5 Marks]

1. What are derived units? [1 Mark]

Answer: The units of derived quantities which can be expressed as a combination of basic units are called derived units.

Teacher's Note:
a) Derived units depend on fundamental units.
b) Examples include square metre for area and cubic metre for volume.

2. How many base units are there in S.I. system? [1 Mark]

Answer: There are seven base units in the S.I. system.

Teacher's Note:
a) The seven base quantities are length, mass, time, electric current, thermodynamic temperature, amount of substance, and luminous intensity.
b) Memorize all seven base units and their symbols.

3. Name the larger units of length? [1 Mark]

Answer: Astronomical unit and light year.

Teacher's Note:
a) Larger units are used to measure astronomical distances.
b) A light year is the distance traveled by light in vacuum in one year.

4. Name the shorter units of length? [1 Mark]

Answer: Angstrom and nanometre.

Teacher's Note:
a) Shorter units are used to measure microscopic dimensions like wavelength of light or atomic sizes.
b) 1 Angstrom equals 10^-10 metres.

5. What is parallax? [1 Mark]

Answer: The apparent change in position of an object with respect to a point when viewed with the left and right eye is known as parallax.

Teacher's Note:
a) Parallax error occurs when the eye is not positioned directly above the scale graduation.
b) Always keep the line of sight perpendicular to the scale to avoid parallax error.

(B) A girl of mass 50 kg is standing on pencil heels each of area of cross-section 1 cm² and an elephant of mass 5000 kg and foot area 250 cm² each, are standing on a floor. Which one will exert more pressure and what is the difference between the pressure exerted by the girl and the elephant? [5 Marks]

Answer:
Weight of the girl = 50 kgf = 50 × 10 = 500 N.
Area of the heels = 2 × 1 cm² = 2 cm² = 2 / 10,000 m².
Pressure exerted by the girl = W / A = 500 / (2 / 10,000) = 2,500,000 Pa.
Weight of the elephant = 5000 kgf = 5000 × 10 = 50,000 N.
Area of the feet = 4 × 250 cm² = 1000 cm² = 1000 / 10,000 m² = 0.1 m².
Pressure exerted by the elephant = W / A = 50,000 / 0.1 = 500,000 Pa.
Difference in pressure = 2,500,000 Pa - 500,000 Pa = 2,000,000 Pa.
Hence, the girl will exert more pressure than the elephant.

Teacher's Note:
a) Convert all areas from square centimetres to square metres by dividing by 10,000.
b) Notice how a smaller surface area results in a tremendously higher pressure, even with a smaller total weight.

Question 5

(A) Answer in one sentence: [5 Marks]

1. Why do all machines require proper care and maintenance? [1 Mark]

Answer: All machines require proper care and maintenance for their efficient and longer use.

Teacher's Note:
a) Maintenance reduces friction and wear and tear of moving parts.
b) Proper lubrication extends machine life.

2. Define 1 Joule of work. [1 Mark]

Answer: 1 Joule is the amount of work done, when a force of 1 newton displaces a body by 1 metre along the line of action of force.

Teacher's Note:
a) Formula: W = Fs.
b) Ensure both force and displacement units are in SI units.

3. When do we say that work is done? [1 Mark]

Answer: Work is said to be done when a force acts on an object and as a result of this force the object gets displaced from its initial position.

Teacher's Note:
a) Both force and displacement in the direction of force are necessary conditions for work.
b) If displacement is zero, work done is zero.

4. What is volume? What is its unit? [1 Mark]

Answer: The space occupied by an object is known as its volume. Its S.I. unit is metre-cubed (m³).

Teacher's Note:
a) Volume measures the three-dimensional space taken up by matter.
b) Litres and millilitres are commonly used practical units.

5. Name the force in action when a potter turns his wheel. [1 Mark]

Answer: When the potter turns his wheel, he applies muscular force.

Teacher's Note:
a) Muscular force is a contact force exerted by skeletal muscles.
b) It is widely used in daily physical activities.

(B) Find the odd one out. [5 Marks]

1. Iron, nickel, cobalt, aluminium [1 Mark]

Answer: Aluminium. Only aluminium is a non-magnetic substance, while the others are magnetic substances.

Teacher's Note:
a) Magnetic substances are strongly attracted by magnets.
b) Aluminium is non-magnetic.

2. Length, mass, area, time [1 Mark]

Answer: Area. Area is a derived quantity, whereas the others are fundamental quantities.

Teacher's Note:
a) Fundamental quantities are basic and independent.
b) Area is derived from length.

3. kelvin, volta, celsius, Fahrenheit [1 Mark]

Answer: volta. Volta is not a unit of temperature; the others are units for measuring temperature.

Teacher's Note:
a) Volta refers to potential difference unit or Alessandro Volta.
b) Kelvin, Celsius, and Fahrenheit measure temperature.

4. Magnetic force, gravitational force, electrostatic force, frictional force [1 Mark]

Answer: Frictional force. Frictional force is a contact force, whereas the others are non-contact forces.

Teacher's Note:
a) Contact forces require physical touch.
b) Non-contact forces act at a distance.

5. Making pores, using lubricants, polishing, using ball bearings [1 Mark]

Answer: Making pores. Making pores is a way to increase friction, whereas the others are ways to decrease friction.

Teacher's Note:
a) Lubricants and ball bearings reduce friction between moving parts.
b) Making pores or rough surfaces increases friction.

Question 6

(A) What is magnetic induction? Explain with the help of a diagram. [5 Marks]

Answer:
The property by which an ordinary piece of iron acquires magnetic properties due to the presence of another magnet is called magnetic induction.
[Figure: Three-part diagram showing a stand with an iron nail and pins at the base. Left: no magnet, pins unattached. Center: bar magnet touched to the nail head, pins clinging to the nail point. Right: magnet removed, pins falling down.]
Spread some iron pins on the base of a stand. These pins are not attracted to the nail. When a magnet is touched to the head of the nail, some pins at the base of the stand cling to the nail. This is because the nail turns into a magnet, and hence, acquires the property of magnetism. This is magnetic induction.
When the magnet is removed from the head of the nail, the pins fall down showing de-magnetism. Hence, the nail acquires magnetism and pins get attracted to it by induction.

Teacher's Note:
a) Magnetic induction precedes attraction in unmagnetized magnetic materials.
b) Emphasize that soft iron loses its magnetism quickly once the external magnet is removed.

(B) Define the following. [5 Marks]

1. One kilogram [1 Mark]

Answer: It is defined as the mass of a cylinder of platinum-iridium alloy kept at the International Bureau of Weights and Measures in Paris.

Teacher's Note:
a) The standard prototype kilogram defines the unit of mass.
b) Note the correct spelling of platinum-iridium alloy.

2. Muscular force [1 Mark]

Answer: Muscular force is the force produced by the muscles of living beings.

Teacher's Note:
a) It is a contact force used in lifting, pushing, and pulling.
b) Animals and humans both exert muscular force.

3. Pressure [1 Mark]

Answer: The force acting per unit surface area is called pressure.

Teacher's Note:
a) Formula: P = F / A.
b) SI unit is Pascal (Pa).

4. Length of a magnet [1 Mark]

Answer: The total distance between the North Pole to the centre and the centre to the South Pole of a magnet is called the length of a magnet.

Teacher's Note:
a) Magnetic length is slightly less than the geometric length of a bar magnet.
b) Poles are situated slightly inside the ends of the magnet.

5. Efficiency [1 Mark]

Answer: Efficiency is the ratio of work done by the machine to the work done on the machine.

Teacher's Note:
a) Efficiency is often expressed as a percentage.
b) Due to friction and energy losses, real machines have efficiency less than 100 percent.

Question 7

(A) Answer the following.

1. Define Kinetic energy and Potential energy? [2 Marks]

Answer:
Kinetic energy: Kinetic energy is the energy possessed by a body by virtue of its motion. It is given by the formula: K.E = 1/2 mv².
Potential energy: Potential energy is the energy possessed by a body by virtue of its position with reference to the Earth. It is given by the formula: P.E = mgh.

Teacher's Note:
a) Distinguish clearly between motion-based energy (kinetic) and position-based energy (potential).
b) Define all variables in the formulae when writing answers.

2. What are the effects of force? [3 Marks]

Answer:
The effects of force are as follows:
1. A force can make a stationary object move.
2. A force can stop a moving object.
3. A force can change the direction of a moving object.
4. A force can change the speed of a moving object.
5. A force can change the shape and size of an object.

Teacher's Note:
a) Force cannot be seen, but its effects can be observed.
b) List at least three to four distinct effects for full credit in 3-mark questions.

(B) Answer the following.

1. What is friction? Write any two advantages of friction? [2 Marks]

Answer:
Friction is the resistance to motion experienced when two surfaces in contact move with respect to each other.
The following are the advantages of friction:
1. It is due to friction that we can walk without slipping.
2. We can hold a pen or a pencil and write due to friction.

Teacher's Note:
a) Friction is a necessary evil; while it causes wear and tear, life is impossible without it.
b) Give clear daily-life examples like writing or walking.

2. What is a screw? Give three uses of screws. [3 Marks]

Answer:
A screw is a rotating (winding) inclined plane.
The following are the three uses of a screw:
1. It is used to hold two pieces of wood or metal tightly.
2. Screw jack is used for lifting a car or a truck, in order to change a punctured wheel.
3. A cork screw is used for pulling out a cork from the bottles of wine or ketchup.

Teacher's Note:
a) A screw works on the principle of an inclined plane wound around a cylinder.
b) Provide practical applications to secure full marks.