Forces in Elevators

The video tutorial explains the forces acting on a person in an elevator. It covers scenarios when the elevator is at rest, accelerating upwards, moving at constant velocity, and decelerating. Key points include the role of gravity and normal force, and how these forces change with the elevator's motion. The tutorial emphasizes that the normal force is not always equal to gravitational force and how this affects the perceived weight of a person in the elevator.

What can be assumed about the state of an elevator when a person enters it?

• The elevator is accelerating.

• The elevator is at rest.

• The elevator is moving downwards.

• The elevator is moving upwards.

What is the acceleration of the elevator when it is at rest?

• Positive

• Negative

• Zero

• Undefined

Which force is commonly mistaken to act on a person inside an elevator?

• Frictional force

• Gravitational force

• Normal force

• Tension force

What happens to the normal force when the elevator starts accelerating upwards?

• It decreases.

• It remains the same.

• It becomes zero.

• It increases.

How does a person feel when the elevator moves with constant velocity?

• Heavier than usual

• Lighter than usual

• Weightless

• Normal weight

What is the state of forces when the elevator moves at a constant speed?

• Unbalanced

• Balanced

• Only gravitational force acts

• Only normal force acts

What happens to the forces when the elevator stops accelerating?

• They become unbalanced.

• They remain unbalanced.

• They become balanced.

• They disappear.

What happens to the normal force when the elevator slows down while moving upwards?

• It becomes zero.

• It becomes greater than gravity.

• It becomes less than gravity.

• It remains equal to gravity.

How does a person feel when the elevator decelerates while moving upwards?

• Heavier than usual

• Lighter than usual

• Normal weight

• Weightless

What is the relationship between normal force and perceived weight in an elevator?

• Normal force is always greater than perceived weight.

• Normal force is always less than perceived weight.

• Normal force is unrelated to perceived weight.

• Normal force determines how heavy or light you feel.