Work, Energy, Power Review

Wiley coyote pushes a 5kg boulder from an initial height of 10m, the boulder rolls down the hill, across the road, and up the hill on the left. The rock is able to reach a height of 17 m before rolling back down. How fast did Wiley have to push the rock to make this happen?

• 140 m/s

• 11.83 m/s

• 350 m/s

• 18.44 m/s

A car travels at a constant velocity, v, up a hill, from point X to point Y, as shown in the diagram to the right. As the car travels from X to Y, its _________________

• PE and KE both remain the same

• PE increases and its KE decreases

• PE increases and its KE remains the same

• PE remains the same and its KE decreases

If a 5kg ball were to have an initial velocity of 50 m/s at point A, and then encounter a hill, what would be the height of the hill?

• 245 m

• 127.55 m

• 2.55 m

• 25 m

At the gym a person is running against a resistance band, as shown in the picture below. What kind of energy does the band posses at this instant?

• Elastic Potential

• Kinetic and Elastic Potential

• Gravitational and Elastic Potential

• Gravitational Potential

• Kinetic

An ice cube and smaller piece of crushed ice are at the same temperature. The thermal energy

• is greater for the ice cube

• is greater for the crushed ice

• is the same for each

There are 4 laws of thermodynamics; the zeroth law describes the direction that energy passes between systems. Which of the following correctly shows the heat transfer between the objects shown?

• 
• 
• 
• 

How much work is done to raise a 3kg jug of water from a chair that is 0.5m high, to a counter that is 1.5m high in 30 seconds?

• 0.5 J

• 1 J

• 3 J

• 30 J

Two students are on the first floor. They each need to carry a box of paper upstairs to their teacher. One carries their box upstairs, the other takes the elevator. In which case was more work done on the boxes?

• They took the same amount of work

• Using the stairs took more work

• Using the elevator took more work

Little Johnny weighs 450 N. He climbs a flight of stairs that is 5 m tall in 10 seconds. How much work did he do?

• 2250 J

• 22500 J

• 225 J

Little Johnny weighs 450 N. He climbs a flight of stairs that is 5 m tall in 10 seconds. How much was his power output?

• 2250 J

• 22500 J

• 225 J