Solutions of NCERT Exemplar Class 8 Chapter 11 – Force And Pressure

 1. Soln:

Answer is (a) Magnitude of force applied by A is greater than that of B.

Explanation:

The magnitude of force applied by A is bigger than that of B as a result of the block moves towards right i.e. towards B.

2. Soln:

Answer is (c) magnetic force alone

Explanation:

As electric current flows through the coil it behaves like an electromagnet which creates magnetic force. Hence the answer is magnetic force alone.

3. Soln:

The answer is (b) electrostatic force.

Explanation:

On combing the hair, comb and hair get oppositely charged due to electrostatic force.

4. Soln:

The answer is (d) Pressure at A < Pressure at B

Explanation:

Increase in water leads to an increase in depth.

5. Soln:

The answer is (d) either a magnetic or an electrostatic force

Explanation: when two objects are experiencing repulsive force because there may be an electrostatic force or a magnetic force.

6. Soln:

The answer is (b) force of friction

Explanation:

Force of attraction acts only when the bodies are in contact.

7. Soln:

Answer is (a) B and C

Explanation:

B and C are at the same level, hence pressure will be the same at B and C.

8. Soln:

Answer is (a) maximum in position A-C

Explanation:

Since the area of contact is minimum pressure will be maximum in A.

9. Soln:

Muscular Force.

10. Soln:

While walking we apply force on the ground.

11. Soln:

Towards the east.

12. Soln:

Answer is Magnetic force.

13. Soln:

Answer is Electrostatic force

14. Soln:

Force of gravity.

15. Soln:

Yes, the force of gravity act on dust particles.