Once you know the basics of Force and Pressure, the next step is to practice numerical and reasoning questions. These 20 difficult MCQs cover pressure calculations, unit conversions, net force, liquid pressure, and atmospheric pressure.

Additionally, let us start with class 8 force and pressure difficult questions.

Practice them with pen and paper. Use the solutions at the end to check steps of your working for class 8 force and pressure difficult questions.

Quick Revision: Formulas and Tips

• Pressure P = F ÷ A. This also gives F = P × A and A = F ÷ P.
• Convert units before calculating: 1 cm² = 0.0001 m² and 1 kPa = 1,000 Pa.
• A block has the same weight on every face, so it exerts the greatest pressure on its smallest face and the least on its largest face.
• Forces along the same line add up if they act in the same direction and are subtracted if they act in opposite directions. A net force of zero means the forces are balanced.
• Balanced forces do not change the state of rest or motion of an object.
• Atmospheric pressure at sea level is about 10⁵ Pa (100 kPa).
• Liquid pressure increases with depth, and at a given depth it acts equally in all directions.

How to use this set: work out each question on paper.

Additionally, compare with the answer key.

For class 8 force and pressure difficult questions if your answer does not match, read the solution and redo calculation.

Practice Questions: 20 Difficult MCQs

1. A force of 300 N acts on an area of 0.15 m². The pressure is:

(a) 45 Pa

(b) 450 Pa

(c) 20,000 Pa

(d) 2,000 Pa

2. A force of 90 N acts on an area of 30 cm². The pressure is:

(a) 3 kPa

(b) 30 kPa

(c) 300 kPa

(d) 0.3 kPa

3. A box weighing 120 N rests on a table with a face of area 0.04 m² touching the table. It is turned so that a face of area 0.01 m² touches the table. The pressure:

(a) becomes half

(b) doubles

(c) becomes 4 times

(d) becomes 16 times

4. In a tug of war, team A pulls the rope with 450 N to the right and team B pulls with 380 N to the left. The net force on the rope is:

(a) 70 N towards A

(b) 830 N towards A

(c) 0 N

(d) 70 N towards B

5. A book weighing 15 N rests on a table. The upward force exerted by the table on the book is:

(a) 0 N

(b) 30 N

(c) 15 N

(d) 7.5 N

6. Three forces act on a box along the same line: 12 N towards the east, 5 N towards the west and 7 N towards the west. The net force is:

(a) zero

(b) 24 N east

(c) 12 N east

(d) 2 N west

7. A tall bottle has three holes at different heights on its side and is filled with water. Water spurts out farthest from the:

(a) lowest hole

(b) top hole

(c) middle hole

(d) all holes equally

8. Atmospheric pressure at sea level is about:

(a) 10 Pa

(b) 100,000 Pa

(c) 1,000 Pa

(d) 10,000,000 Pa

9. Take atmospheric pressure as 10⁵ Pa. The force exerted by air on one side of a tabletop of area 0.5 m² is about:

(a) 5,000 N

(b) 500,000 N

(c) 50,000 N

(d) 5 N

10. A rubber suction cup sticks firmly to a smooth wall because:

(a) of glue on the cup

(b) of gravity

(c) of magnetic force

(d) the outside air pressure is greater than the pressure inside after the air is squeezed out

11. A girl weighing 450 N stands on both feet. Each foot has an area of 150 cm². The pressure on the ground is:

(a) 3,000 Pa

(b) 7,500 Pa

(c) 15,000 Pa

(d) 30,000 Pa

12. A block placed on a face of area 0.02 m² exerts a pressure of 4,000 Pa on the floor. The weight of the block is:

(a) 80 N

(b) 320 N

(c) 20 N

(d) 8 N

13. We cannot drink through a straw that has a hole above the liquid level because:

(a) gravity increases

(b) air enters through the hole and the pressure inside the straw does not fall below the outside pressure

(c) of friction

(d) the straw gets blocked

14. A glass filled to the brim with water is covered with a card and turned upside down. The card stays in place and the water does not spill. This is because of:

(a) magnetic force

(b) friction between the card and the glass

(c) gravity holding the water

(d) atmospheric pressure pushing the card upward

15. Two metal hemispheres were joined and the air inside was pumped out. Teams of horses could not pull them apart because:

(a) of magnetic attraction

(b) of glue

(c) atmospheric pressure outside pushes the two halves together

(d) of gravity

16. A camel walks easily on desert sand because its feet:

(a) are lighter than other animals’ feet

(b) are broad, so the pressure on the sand is small

(c) are on hard ground

(d) are sticky

17. A cart moves at constant speed on a straight road. The engine pushes it forward with 500 N and friction acts backward with 500 N. Which statement is correct?

(a) The net force is 1,000 N forward

(b) The cart speeds up

(c) The cart stops at once

(d) The net force is zero and the speed stays constant

18. At a given depth inside a liquid, the pressure is:

(a) greatest downward

(b) greatest upward

(c) the same in all directions

(d) zero sideways

19. Which changes will increase the pressure exerted by a block on a table?

(i) Increasing the weight, keeping the area the same

(ii) Decreasing the area of contact, keeping the weight the same

(iii) Increasing the area of contact, keeping the weight the same

(iv) Decreasing the weight, keeping the area the same

(a) (i) and (ii)

(b) (i) and (iii)

(c) (ii) and (iv)

(d) (iii) and (iv)

20. When more air is pumped into a football, the pressure inside it increases because:

(a) air becomes heavier

(b) more air particles hit the inner walls more often

(c) gravity increases

(d) the ball becomes hot

Answers and Solutions

Q	Ans	Solution
1	(d)	P = F ÷ A = 300 ÷ 0.15 = 2,000 Pa.
2	(b)	30 cm² = 0.003 m². P = 90 ÷ 0.003 = 30,000 Pa = 30 kPa.
3	(c)	Pressure = weight ÷ area. Before: 120 ÷ 0.04 = 3,000 Pa. After: 120 ÷ 0.01 = 12,000 Pa. The pressure becomes 4 times.
4	(a)	Net force = 450 − 380 = 70 N, in the direction of the stronger team (A).
5	(c)	The book is at rest, so the forces are balanced. The upward force equals the weight, 15 N.
6	(a)	Forces towards the west = 5 + 7 = 12 N. Net = 12 − 12 = 0. The forces are balanced.
7	(a)	Pressure increases with depth, so the lowest hole (greatest depth) gives the strongest jet.
8	(b)	Atmospheric pressure at sea level is about 1 × 10⁵ Pa (roughly 100,000 Pa).
9	(c)	F = P × A = 10⁵ × 0.5 = 50,000 N.
10	(d)	Pressing the cup removes air, so the higher outside air pressure holds it against the wall.
11	(c)	Total area = 2 × 150 = 300 cm² = 0.03 m². P = 450 ÷ 0.03 = 15,000 Pa.
12	(a)	Weight = P × A = 4,000 × 0.02 = 80 N. (On a 0.08 m² face the pressure would be 1,000 Pa.)
13	(b)	Air entering the hole keeps the pressure inside the straw equal to the outside pressure, so the liquid is not pushed up.
14	(d)	Atmospheric pressure acts upward on the card and holds it in place.
15	(c)	With almost no air inside, the atmospheric pressure outside pushes the halves together strongly.
16	(b)	Broad feet have a large area, so the pressure on the sand is small and the camel does not sink.
17	(d)	The forces are equal and opposite, so the net force is zero. The cart continues at constant speed.
18	(c)	At a given depth, liquid pressure acts equally in all directions.
19	(a)	Pressure = force ÷ area. It increases with more force (weight) or with less area.
20	(b)	More air particles strike the inner walls more often, so the gas pressure increases.

Keep Practicing

Try the other practice sets for this chapter:

• Force and Pressure MCQs Class 8: 20 Easy Questions + Answers
• Class 8 Olympiad Physics: 50 Force and Pressure MCQs (ISO Style)

Found a mistake or want more chapters? Leave a comment below and we will update this post.