Chapter 5 - Energy Review

In the equation for Gravitational Potential Energy, what does "g" represent?

• mass of the substance in grams

• acceleration of Earth's gravity (9.8 meters per second squared)

• gigajoules of energy stored

• gravitational force between the two objects

All energy is measured in what unit?

• Joules (J)

• Watts (W)

• Newtons (N)

• Kilograms (kg)

The Mechanical Energy of an object is the combination of what? (Choose all correct answers)

• Kinetic Energy

• Gravitational Potential Energy

• Thermal Energy

• Elastic Potential Energy

What force causes Gravitational Potential Energy to be converted to Kinetic Energy?

• Friction

• Gravity

• Thrust

• Drag

What force causes Kinetic Energy to transform into Thermal Energy?

• Friction

• Gravity

• Thrust

• Drag

How high is a building if a 75 kg box resting at the top has 73500 Joules of potential energy?

• 980 meters

• 100 meters

• 10 meters

• 98 meters

How much kinetic energy does a 50 gram dart have if it is traveling at 30 meters per second?

• 22.5 joules

• 22,500 joules

• 45 joules

• 45,000 joules

Police were investigating the scene of a 5,000 kg car crashing into a buiding. They determined from the damage that the collision delivered 1,562,500 joules of energy. How fast was the car driving?

• 25 m/s

• 625 m/s

• 55.9 m/s

• 235.2 m/s

What is another unit that is the same as a Joule, but is sometimes used to label Work?

• Newton-meter

• kilogram-meter per second

• Watt

• Newton

A 50 kg student was late to science class and was running up the 5 meter high staircase. She was able to make it up the staircase in 3 seconds. How much Power did her legs deliver up the stairs?

• 816.7 Watts

• 83.3 Watts

• 7350 Watts

• 7.9 Watts