Unit 2 Module I Work, Power, Energy

Which of the following is an example of the conversion of kinetic energy into gravitational potential energy?

• a person parachuting out of an airplane

• a car racing around an oval track

• a person skiing down a hill

• a person walking up a hil

Which of the following best defines energy?

• the ability to do work

• the resistance to motion

• how fast an object moves

• amount of force in a given time

Which of the following describes a transfer of energy through work?

• A student carries a heavy backpack one km.

• A laboratory burner is used to heat 250 mL of water to boiling.

• A woman pushes a luggage cart in an airport over a distance of 100 m.

• A man pushes on a large piece of furniture for 15 min, but it does not move.

The table shows different forces and distances that employees in a factory used to lift boxes. Which employee did the most work while lifting boxes?

• Cassie

• Rafael

• Ayanna

• Michael

Which of the following is an example of energy being used to do work?

• A woman sits on the edge of a bench.

• A soccer ball rests at the top of a hill.

• A boy holds a fishing pole over the water.

• A girl climbs up a ladder holding a paint can.

A lightbulb uses 2,000 J of energy in 1 min and 20 s. What is the power of the lightbulb?

• 25 W

• 50 W

• 60 W

• 100 W

Which of the following has kinetic energy?

• a book sitting on a shelf

• hat and gloves on a table

• a child kicking a soccer ball

• cars parked in a parking lot

What term describes the energy that is stored due to the height of an object from the ground?

• kinetic energy

• chemical energy

• mechanical energy

• gravitational potential energy

Three rocks are rolling down a hill at the same speed. Rock 1 has a mass of 1 kg; rock2 has a mass of 1.5 kg, and rock 3 has a mass of 3 kg. Which rock has the most kinetic energy?

• rock 1

• rock 2

• rock 3

• all three rocks have the same kinetic energy

The following table shows information about three different objects sitting on a bookshelf.Some data are missing from the table. What is the gravitational potential energy of object 1?

• 7.35 J

• 117.6 J

• 176.4 J

• 196 J