AKS 5b1 Calculating PE & KE

A 68 kg circus performer sits on a 4.2 m tall elephant. Find the potential energy of the performer.

• 2798.9 J

• 285.6 J

• 16.2 J

• 29.1 J

A 5 kg dog runs at 2.5 m/s. Find the kinetic energy of the dog.

• 6.25 J

• 12.5 J

• 15.6 J

• 122.5 J

Two bowling balls of equal mass are dropped from two different ledges. Ball B is dropped from twice the height of Ball A. How will their final kinetic energies compare immediately before they hit the ground?

• Ball B will have twice as much KE as ball A.

• Ball B will have four times as much KE as ball A.

• Ball B will have more KE by a factor of 2

• Ball B will have the same KE as ball A.

The skateboarder shown above has a potential energy of 2,800 J at a height of 4 meters. How much GPE and KE will she have when she is only 2 meters up?

• KE: 1000 J; PE: 1800 J

• KE: 1400 J; PE: 1400 J

• KE: 2800 J; PE: 0 J

• KE: 1400 J; PE: 0 J

The skateboarder shown above has a potential energy of 2,800 J at a height of 4 meters. Calculate the mass of the skateboarder.

• 700 kg

• 285.7 kg

• 71.4 kg

• 142.8 kg

A 5kg ball is held at the top of a frictionless ramp as shown in the picture. What is the starting potential energy of the ball?

• 0 J

• 490 J

• 980 J

• 1960 J

What is the kinetic energy of the ball when it reaches a height of 0m (bottom of the ramp)?

• 0 J

• 490 J

• 980 J

• 1960 J

How fast is the ball going at the bottom of the ramp?

• 14 m/s

• 19.8 m/s

• 392 m/s

• 980 m/s