PSCI

A car moves 2 times as fast as another identical car. Compared with the slower car, the faster car ha

16 times the kinetic energy

If you exert 100J to lift a box in 50s your power output is

2W

A 2-kg mass that weighs 20N has 40J of potential energy relative to the ground. What is the height?

2m

A music console is pushed 2 m by a force of 20 N. The work done on the console is

40J

A piece of taffy slams into and sticks to another identical piece of taffy at rest. The momentum of the two pieces of taffy stick together after the collision is the same as it was before the collision. Kinetic energy is a different story, for part of it turns into heat. What percentage of the kinetic energy converts into heat?

50%

A popper is turned inside out so that it has 60 J of potential energy. When it pops is firedits kinetic energy ideally

60J

Whereas impulse involves the time that a force acts, work involves the

distance that a force acts

The amount of potential energy possessed by an elevated object is

equal to the kinetic energy it will acquire when freely falling to its reference level; relative to a chosen reference level; equal to the work done in lifting it

A car that travels twice as fast as another when braking to a stop will skid

four times as far

A block of ice sliding down an incline has half its maximum kinetic energy

half-way down

An object that has kinetic energy must be

moving

A ball rolling down an incline has its maximum potential energy at

the top

If you do work on an object in half the time, your power output is

twice

An object lifted 10 m gains a certain amount of potential energy. If it is lifted 20 m, its gain in potential energy is

twice as much

When you push an object a certain distance while applying twice the, you do

twice as much work