Work and Energy

Which of the following is the BEST definition of work in physics?

• The force applied to an object.

• The distance an object moves.

• The force applied to an object multiplied by the distance it moves in the direction of the force.

•  The energy an object possesses due to its motion.

A student pushes a box across a smooth floor. Which of the following statements is TRUE.

• Work is done only if the box moves.

• Work is done only if the student applies a force.

• Work is done only if the student applies a force and the box moves

• Work is done only if the student applies a force and the box moves in the direction of the force.

1. Which of the following is an example of kinetic energy?

•  A stretched rubber band.

• A book resting on a shelf.

• A moving car.

• A compressed spring.
  

Which of the following best defines the difference between work and energy?

• Work is the capacity to cause change, while energy involves applying force.

• Energy is the ability to do work, while work is the transfer of energy through displacement.

• Work is the ability to do energy, while energy is the transfer of displacement.

• Energy and work are the same and involve the displacement of an object.

Which of the following conditions must be met for work to be done on an object?

• A force must be applied without causing motion.

• The force and displacement must be in opposite directions.

• A force must cause displacement in the direction of the force.

• Energy must be transferred to the object without any force applied.

If an object’s mass doubles while its velocity stays the same, how does its kinetic energy change?

• It remains the same.

• It doubles.

• It halves.

• It quadruples.

The formula KE= 1/2mv tells us that kinetic energy depends on which of the following factors?

• Mass and acceleration

• Force and displacement

• Mass and velocity

• Force and velocity

1. A box is pushed across a floor with a force of 50 N, causing it to move 4 meters in the direction of the force. How much work is done on the box?

• 0 J

• 12.5 J

• 50 J

• 200 J

1. A person applies a horizontal force of 65 N to push a box across a 5-meter surface. How much work is done by the person?

• 0 J

• 65 J

• 325 J

• 600 J

1.  A cyclist has a kinetic energy of 500 J while riding at a speed of 5 m/s. What will the kinetic energy be if the cyclist doubles their speed?

• 500 J

• 1000 J

• 1500 J

• 2000 J