Physics Chapter 7 Hw Part 1

W =

The work done in pushing a TV set a distance of 2 m with an average force of 20 N is

The work you do when pushing a shopping cart twice as far while applying the same force is

The work you do when pushing a shopping cart twice as far while applying twice the force is

The work you do when pushing a shopping cart a given distance while applying twice as much force is

No work is done by gravity on a bowling ball that rolls along a bowling alley because

A 1000-kg car and a 2000-kg car are hoisted to the same height. Raising the more massive car requires

The unit kilowatt-hour is a unit of

One kilowatt-hour represents

Which task requires more work? lifting the 25-kg sack 4 meters lifting the 50-kg sack 2 meters

The amount of work done on a heavy box carried by Nellie across a room at a constant speed

If you do work on a skateboard loaded with friends in one-third the usual time, you expend

The power expended doing 100 J of work in 50 s is

The power required to exert 4-N force over 3 meters in 2 seconds is

Both a 50-kg sack is lifted 2 meters from the ground and a 25-kg sack is lifted 4 meters in the same time. The power expended in raising the 50-kg sack is

A toy elevator is raised from the ground floor to the second floor in 20 seconds. The power needed using 1000 J of work, is

An object has gravitational potential energy due to its

Relative to an initial height, an object raised twice as high has a gravitational potential energy

A crate of grapes lifted 10 meters gains 200 J of potential energy. If the same crate is instead lifted 20 meters, its gain in potential energy is

When a drawn bow of potential energy 40 J is fired, the arrow will ideally have a kinetic energy

A clerk can lift cylindrical packages 1 meter vertically, or can roll them up a 2-meter-long ramp to the same elevation. With the ramp, the applied force required is about

A 2-kg ball is held 4 m above the ground. Relative to the ground its potential energy is

A 2-kg box of taffy candy has 40 J of potential energy relative to the ground. Its height above the ground is

The ram of a pile driver drops onto the top of an iron beam, driving it partway into the ground. The distance that the beam sinks into the ground depends on the

An object that has kinetic energy must be

Two identical golf carts move at different speeds. The faster cart has twice the speed and therefore has

A feather and a coin dropped in a vacuum fall with equal

A melon is tossed straight upward with 100 J of kinetic energy. If air resistance is negligible the melon will return to its initial level with a kinetic energy of

A melon is projected into the air with 100 J of kinetic energy in the presence of air resistance. When it returns to its initial level its kinetic energy is

Danny Diver weighs 500 N and steps off a diving board 10 m above the water. Danny hits the water with kinetic energy of

Which has greater kinetic energy?

Neglecting air resistance, Sammy Smarts on a high ladder releases a ball that strikes the ground with 100 J of kinetic energy. If he were to instead throw the ball straight upward, it will soon reach the ground with a kinetic energy of

If a Ping-Pong ball and a golf ball both move in the same direction with the same amount of kinetic energy, the speed of the Ping-Pong ball must be

Two identical particles move toward each other, one twice as fast as the other. Just before they collide, one has a kinetic energy of 25 J and the other 50 J. At this instant their total kinetic energy is

When Joshua brakes his speeding bicycle to a stop, kinetic energy is transformed to