force and pressure class 8.pdf_20250817_225016_0000.pdf

Test paper

1. LEARNIVIO
8th
science
REVISION TEST
GENERAL INSTRUCTIONS • SYLLABUS :
Chapter : Force and Pressure
Topic : Full Chapter
Duration: 1 Hr M.M : 34
Q.1 – Q.9 (MCQ) – 1 mark each
(9×1 = 9 marks)
1.
2.
In a tug of war, the rope moves towards Team A. This means:

(a) Force applied by A is greater than that of B.
(b) Force applied by A is smaller than that of B.
(c) Net force is zero. (d) Force applied by both
teams is equal.
In the given electric bell circuit, the hammer moves because of:
(a) Gravitational force
(b) Magnetic force
(c) Electrostatic force

2. (a) B and C
(b) A and B
(c) C and D
(d) A and C
(d) Frictional force
3. During dry weather, hair sometimes stands apart while combing due to:
(a) Force of gravity
(b) Magnetic force
(c) Force of friction
(d) Electrostatic force
4. Water pressure in a container:
(a) Increases with depth
(b) Decreases with depth
(c) Remains the same at all depths
(d) Is maximum at the surface
5. Two objects repel each other. This could be due to:
(a) Frictional force
(b) Electrostatic force
(c) Magnetic force
(d) Either (b) or (c)
6. A water tank has four taps fixed at points A, B, C, D as shown in Fig. The
water will flow out at the same pressure from taps at :
7.When we press the bulb of a dropper with its nozzle kept in water, air in the
dropper is seen to escape in the form of bubbles. Once we release the

3. 10.
(a) maximum in position A
(b) maximum in position B
(c) maximum in position C
(d) equal in all cases.
9.When a force applied on an object are equal and opposite, then this force
A. May move the object.
B. Change the shape of the object and may move the object.
C. May stop a moving object.
D. Do not move the object but may cause a change in its shape.
pressure on the bulb, water gets filled in the dropper. The rise of water in the
dropper is due to :
(a) pressure of water
(b) gravity of earth
(c) shape of rubber bulb
(d) atmospheric pressure
8. A brick is kept in three different ways on a table as shown in Fig. The
pressure exerted by the brick on the table will be :
Q.10 – Q.11 (Assertion–Reason) – 1 mark each
(2×1 = 2 marks)
Assertion (A): The relationship between force, pressure, and area is
given by P=F/A.

4. Reason (R): The SI unit of pressure is N/m2 or Pascal (Pa).

14.What is atmospheric pressure?
(a) A and R both are true, and R is the correctexplanationofA.
(b) A and R both are true, but R is not the correct explanationofA.
(c) A is true, R is false. (d) A is false, R is true.
11.Assertion (A): Gravitational force acts only on large bodies like planets.
Reason (R): Small objects do not have gravity. (a) Both A and
R are true, R is the correct explanation. (b) Both A and R are
true, but R is not the correct explanation. (c) A is true, R is
false. (d) A is false, R is true.
12. A girl pushes a cart to the east. In which direction should her friend push to
make it move faster in the same direction?
13. True and false
a. Friction opposes the relative motion between two surfaces in contact.
b. A force can act on an object with or without being in contact with it.
15. Two rods of the same weight and equal length have different thickness. They
are held vertically on the surface of sand as shown in Fig.
Which one of them will sink move? Why?
Q.15 (Short Answer) – 3 marks
(1×3 = 3 marks)
Q.12 – Q.14 (Very Short Answer) – 2 marks each
(3×2 = 6 marks)

5. Q.18 (Case-Based) – 4 marks
(1×4 = 4 marks)
Read the passage and answer the following questions:
The discovery of atmospheric pressure gives a fact that air has weight. The weight of
the atmosphere presses down on the earth’s surface and creates pressure on it. The
Q.16 – Q.17 (Long Answer) – 5 marks each
(2×5 = 10 marks)
16.
17.Itis much easier to burst an inflatedballoon with a needle than with a finger.
Explain why, using the concept of pressure.
A stone weighs 500 N. Calculate the pressure exerted by it, if it makes
contact with a surface of area 25 cm2.

6. a) We know that there is a huge amount of atmospheric pressure on us. But we do
not experience its effect. Why?
b) Why do some people feel their ears “popping” at the top of the mountain?
pressure at any point exerted by the weight of the air above is called atmospheric
pressure. The atmospheric pressure on the earth's surface at sea level is one hundred
thousand pascals i.e.100 K Pa. The atmospheric pressure at a place decreases with
an increase in altitude. The atmospheric pressure at a place is the force exerted by the
weight of the air column above that place. As we go up the length of the air column
above us decreases. This means that its weight and the atmospheric pressure are
smaller at higher places than at sea level. If the pressure of the atmosphere is
removed suddenly, our blood vessels and tissues will rupture due to the pressure of
the blood and other fluids inside. Thus, the spacemen also wear special pressurised
suits as in space there is no air and hence, no air pressure. At the top of a mountain,
some people can feel their ears “popping” due to a decrease in air pressure. The ears
pop to balance the difference in pressure inside and outside the body.