Question

true or false:
1-The direction of kinetic friction force is opposite to the motion of the particle.

2-The vertical force on the displacement of the body does not work.

3-The direction of kinetic friction force is in the direction of the particle's motion.

4-Flexibility is the resistance of solid objects to change in shape or size when exposed to stress.

5-Ying's modulus of a substance depends on the type of material only and works in the linear region.

Answer 1

Solution:

1. The direction of kinetic friction force is opposite to the motion of the particle – True

2. The vertical force on the displacement of the body does not work–True

3. The direction of kinetic friction force is in direction of the particles motion –False

4.Flexibility is resistance of solid objects to change in shape or size when exposed to stress –False

5.Youngs Modulus of a substance depends on the type of material only and works in the linear region–True

Explanation : 3. Direction of kinetic friction force is always opposite to the motion of the particle.

Explanation : 4. Flexibility is the property of solid objects which has ability to change in shape or size when exposed to stress.