Kinetic Energy and Work Principles

The video explores the concepts of work and energy, explaining how they provide a new perspective on physical phenomena. It discusses Newton's second law, the relationship between force and acceleration, and how work done on an object affects its kinetic energy. The video also covers negative work and its role in energy removal, providing examples to illustrate these concepts. Finally, it derives the work-energy theorem mathematically, showing how work done on a body changes its kinetic energy.

What happens to a bowling ball's speed when a force is applied to it?

• It stops moving.

• It decreases.

• It increases.

• It remains constant.

What is the effect of doing positive work on an object?

• It decreases the object's kinetic energy.

• It stops the object.

• It increases the object's kinetic energy.

• It has no effect on the object's kinetic energy.

When you catch a ball and your hand moves back, what type of work is being done?

• Neutral work

• No work

• Negative work

• Positive work

What happens to a ball's kinetic energy when gravity does positive work on it?

• The kinetic energy decreases.

• The ball stops moving.

• The kinetic energy increases.

• The kinetic energy remains the same.

How does gravity affect a ball thrown upwards?

• Gravity does positive work, increasing kinetic energy.

• Gravity does negative work, decreasing kinetic energy.

• Gravity has no effect on kinetic energy.

• Gravity stops the ball immediately.

What is the total work done on a cupboard when it is pushed on a rough floor and remains at rest?

• Positive work is done.

• Negative work is done.

• Infinite work is done.

• Zero work is done.

Why does the kinetic energy of a puppy remain unchanged when lifted slowly?

• Only negative work is done.

• Only positive work is done.

• Positive and negative work cancel each other out.

• No work is done.

What is the relationship between work done and kinetic energy according to the work-energy theorem?

• Work done is unrelated to kinetic energy.

• Work done is always greater than kinetic energy.

• Work done is always less than kinetic energy.

• Work done equals the change in kinetic energy.

How can you calculate the work done by a force?

• By multiplying force by time.

• By multiplying force by displacement.

• By dividing force by displacement.

• By adding force and displacement.

What happens to kinetic energy if the total work done by multiple forces is zero?

• Kinetic energy becomes negative.

• Kinetic energy remains unchanged.

• Kinetic energy decreases.

• Kinetic energy increases.