Unit 4: Energy Review

What is the Law of Conservation of Energy?

• Energy can be created, but it can't be destroyed.

• Energy can be destroyed, but it can't be created.

• Energy can be created and destroyed.

• Energy cannot be created or destroyed.

Answer explanation

The Law of Conservation of Energy states that energy cannot be created or destroyed.

Tags

NGSS.HS-PS3-2

What is the formula for work?

• Work = Distance x Force

• Work = Distance/Force

• Work = Force/Distance

• Work = Distance x time

Answer explanation

The formula for work is Work = Distance x Force. This formula calculates the amount of work done by multiplying the distance and the force applied.

The SI unit for work that is equal to one Newton-meter is __________________.

• Newton

• meter

• Joule

• Watt

Answer explanation

The SI unit for work that is equal to one Newton-meter is Joule. Joule is the correct choice because it represents the amount of work done when a force of one Newton is applied over a distance of one meter.

If you walk for one mile, and later you walk for two miles, how much work did you do in the 2 mile walk compared to the one mile walk?

• You did the same amount of work because your force didn't change.

• You did twice as much work because you walked twice as far.

• You did half as much work because you walked twice as far.

• There is no way of knowing.

Answer explanation

The work done is directly proportional to the distance covered. Since you walked twice as far, you did twice as much work.

Tags

NGSS.HS-PS3-2

How many Joules of work are done if you carry a 30N rock for 10 meters?

• 300 Joules

• 3 Joules

• 0.33 Joules

• 0 Joules

Answer explanation

To calculate the work done, multiply the force (30N) by the distance (10m). The correct choice, 300 Joules, is obtained by multiplying 30N by 10m.

What is the unit for Kinetic Energy?

• Joules

• Watts

• Meters

• Seconds

Answer explanation

The unit for Kinetic Energy is Joules, which is a measure of energy. It is the correct choice because it is the standard unit used to quantify kinetic energy.

Tags

NGSS.HS-PS2-1

What is the unit for Potential Energy?

• Joules

• Watts

• Meters

• Seconds

Answer explanation

The unit for Potential Energy is Joules. Joules is the correct choice because it is the standard unit for measuring energy.

What is the formula for Kinetic Energy?

• KE = mgh

• KE = weight(height)

Answer explanation

The formula for Kinetic Energy is KE = 0.5(mass)(velocity^2). This formula represents the relationship between mass and velocity in calculating kinetic energy.

What is the formula for Potential Energy?

• PE = mgh

• PE = weight(height)

• PE = 0.5(mass)(velocity*squared)

• PE = 1/2(mass)(velocity*squared)

Answer explanation

The formula for Potential Energy is PE = mgh. This equation represents the product of mass, gravitational acceleration, and height.

Tags

NGSS.MS-PS3-2

A spring in compressed to 55J of elastic potential energy. When released, what will the Kinetic Energy be?

• 55 Joules exactly.

• More than 55 Joules.

• Less than 55 Joules.

• There's no way of knowing.

Answer explanation

When a spring is released, all of its potential energy is converted into kinetic energy. Therefore, the kinetic energy will also be 55 Joules exactly, which is the same as the initial potential energy.

Tags

NGSS.HS-PS2-1