Work, Energy & Power

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Multiple Choice

Which equation should be used to calculate work ?

• W = Fd

• W = F + d

• F = Wd

• W = F/d

​In both cases shown, there is no work done.

Multiple Select

In which cases was work done? Choose all that apply.

• a book is lifted from the floor to the table

• a desk is pushed across the floor

• a computer is sitting on the desk

Fill in the Blanks

A force perpendicular to the direction of motion of an object cannot do

on the object.

Multiple Choice

Which of the following statements about the joule is correct?

• A joule is the SI unit of force.

• A joule is the SI unit of energy.

• A joule is equal to 1 newton per meter.

• A joule is used to measure speed.

Multiple Select

Select all correct statements about the relationship between force, distance, and the direction of work.

• If force is perpendicular to distance, no work is done.

• Work is always done regardless of the direction of force.

• A force that is slowing an object down or stopping movement causes negative work.

• If an object is moving but there is not a force acting on it, work is still being done.

• A force on an object that doesn't cause motion does NO work.

Fill in the Blanks

Power is defined as the rate at which

is done over a period of time.

Multiple Choice

Which of the following is the correct definition of a watt?

• 1 watt = 1 joule/second

• 1 watt = 1 newton/second

• 1 watt = 1 joule/minute

• 1 watt = 1 newton/meter

Multiple Choice

Kinetic energy depends on which of the following factors?

• Mass and velocity of the object

• Only the mass of the object

• Only the velocity of the object

• The color of the object

Fill in the Blanks

The formula for kinetic energy is KE =

mv^2.

Open Ended

If a 1000 kg car increases its speed from 10 m/s to 30 m/s, how does its kinetic energy change? Use the example provided to explain your answer.

Fill in the Blanks

When a hammer strikes a nail, the hammer’s kinetic energy is converted into

, which pushes the nail into the wood.

Multiple Choice

Using a hammer with a 600g head moving at 4 m/s to drive a 5mm nail into a piece of wood, what is the force exerted on the nail on impact?

• 960 N

• 120 N

• 600 N

• 480 N

Open Ended

Explain the difference between elastic potential energy and gravitational potential energy, providing an example of each.

Fill in the Blanks

Gravitational potential energy is given by the formula PE =

.

Multiple Choice

Compare the potential energy of a car at the top of a 45m cliff with the kinetic energy of a car moving at 30 m/s. Which is greater and by how much?

• Potential energy is greater by 9,000 J

• Kinetic energy is greater by 9,000 J

• Both are equal

• Potential energy is greater by 441,000 J

Multiple Select

Which of the following are examples of potential energy?

• A book on the table

• A car moving at constant speed

• A stretched spring

• A skier at the top of a slope

Open Ended

How does the height of an object affect its gravitational potential energy?

Multiple Choice

Which statement best describes the Law of Conservation of Energy?

• Energy can be created and destroyed.

• Energy cannot be created or destroyed, but can change forms.

• Energy can only be created, not destroyed.

• Energy can only be destroyed, not created.

Open Ended

Explain why the conservation of energy is significant if the laws of nature are the same at all times.

Multiple Choice

In the scenario of a car rolling down a hill into a valley, which forms of energy are being converted?

• Potential energy to kinetic energy and vice versa

• Kinetic energy to thermal energy

• Potential energy to chemical energy

• Kinetic energy to electrical energy

Multiple Choice

At which labeled position (A, B, C, D, or E) does the skateboarder have the greatest kinetic energy?

• A

• B

• C

• D

Fill in the Blanks

At the lowest point of the pendulum's swing, the kinetic energy is ___ and the potential energy is ___.

Open Ended

A parcel of mass 4 kg slides down a smooth curved ramp from a height of 5 m. Calculate the speed of the parcel when it reaches the bottom and explain the energy transformation involved.

Fill in the Blanks

Energy can neither be created nor

.

Open Ended

Summarize one key idea you learned about energy from today's lesson and explain why it is important in our everyday lives.