Kinetic Energy

A 20.0 kg object is at rest, and then speeds up to 16.0 m/s. How much work was done on this system?

2,560 J

What is the kinetic energy of a 620.0 kg roller coaster moving with a velocity of 9.00 m/s?

25,100 J

A 60.0 kg runner is moving at 6.00 m/s and speeds up to 9.00 m/s. The runner's change in kinetic energy is 1,350 J. How much work was done?

A. -2,430 J wrong B. -1,350 J C. 1,350 J wrong D. 2,430 J

Four vehicles are traveling on the same road. Which vehicle most likely has the greatest kinetic energy?

A. a compact car traveling at a velocity of 10 m/s B. a pickup truck traveling at a velocity of 25 m/s wrong C. a minivan traveling at a velocity of 10 m/s wrong D. a motorcycle traveling at a velocity of 25 m/s

Which formula can be used to find velocity if kinetic energy and mass are known?

D. v = 2KE/m

Lenny wrote the steps he used to find the mass of an object with 400 J of energy moving at a velocity of 8 m/s. 1. Find the square of 8 m/s, which is 64 m2/s2. 2. Divide kinetic energy, 400 J, by 64 m2/s2, which is 6.25 J per m2/s2. 3. Divide 6.25 J per m2/s2 by 2 to get a mass of 3.125 kg. Which best describes Lenny's error?

In Step 3, he should have multiplied 6.25 J per m2/s2 by 2 instead of dividing it by 2.

According to the work-energy theorem, the amount of work done can be determined using which formula?

W = /\ KE = 1/2m (v2f - v2i)

The diagram shows a side view of a skateboard ramp. At which labeled points would the skateboarder have the most kinetic energy?

X and Y