Work and Energy Review

Match

Match the term to its correct definition::

• Work

• Kinetic Energy

• Potential Energy

• Power

• Joule

The product of force and displacement

The energy of a body due to its motion

The energy stored in an object due to its position

The rate at which work is done

A unit of energy

• The product of force and displacement

• The energy of a body due to its motion

• The energy stored in an object due to its position

• The rate at which work is done

• A unit of energy

Open Ended

When is no work done, even if you’re applying a force?

Open Ended

Give one example of positive work and one of negative work.

Open Ended

What does it mean if mechanical energy is conserved?

Multiple Choice

A student pushes a box with a force of 50 N across a floor for 4 meters at an angle of 0°.
How much work is done?

• 250 J
• 150 J
• 100 J
• 200 J

Multiple Choice

A 60 kg skateboarder moves at 5 m/s.
What is his kinetic energy?

• 300 J
• 750 J
• 1000 J
• 500 J

Multiple Choice

A rock is lifted to a shelf 2 meters high. It has a mass of 10 kg.
What is its gravitational potential energy?

• 196.2 Joules
• 302.4 Joules

• 114.6 Joules

• 50.2 Joules

Open Ended

Describe how energy changes as a ball is thrown straight up and comes back down.

Multiple Choice

A 2.0 kg object is dropped from a height of 10 meters.
What is its speed just before it hits the ground (neglect air resistance)?

• 20.0 m/s
• 14.0 m/s
• 9.8 m/s
• 5.0 m/s

Multiple Choice

A student runs up a flight of stairs 5.0 meters high in 7.0 seconds. Her mass is 55 kg. How much work did she do?

• 3223.25 J

• 2697.75 J
• 2017.66 J

• 1502.45 J

Multiple Choice

A student runs up a flight of stairs 5.0 meters high in 7.0 seconds. Her mass is 55 kg.
What was her power output?

• 250.23 W

• 506.43 W

• 384.32 W
• 321.62 W

Multiple Choice

A spring with a spring constant of 200 N/m is compressed by 0.1 m. What is the elastic potential energy stored in the spring?

• 2 Joules
• 0.5 Joules
• 0.1 Joules
• 1 Joule

Multiple Choice

A toy car with a mass of 0.50 kg is launched by a compressed spring. The spring does 2.0 J of work on the car. What is the car's speed just after it is launched?

• 4.02 m/s

• 3.50 m/s
• 1.57 m/s

• 2.83 m/s

Multiple Choice

A car engine provides 1.2 × 10⁵ J of work in 8.0 seconds.
What is the average power of the engine in watts?

• 15000 W
• 20000 W
• 18000 W
• 12000 W

Multiple Choice

A sled is pulled across snow with a 100 N force at an angle of 30° to the horizontal for 20 meters.
How much work is done by the pulling force?

• 173.2 J
• 152.5 J

• 203.6 J

• 104.7 J