work and energy copy
Which of the following is not a unit for power? -(Joule)x(Second) -Watt -(Newton)x(meter)/(second) -Horsepower
(Joule)x(Second)
How many Joules of energy are in one kilowatt-hour?
3.6 megajoules
A feather and a coin dropped in a VACUUM fall with equal _____.
accelerations
Strictly speaking, a car will burn more gasoline if the car radio is turned on. This statement is _____.
always true
Two identical arrows, one with twice the SPEED of the other, are fired into a hay bale. The faster arrow will penetrate _____.
four times as far as the slower arrow
An object that has potential energy has this energy because of its _____.
location
An object that has kinetic energy must be _____.
moving
An object is moved upwards 2 meters and gains a certain amount of potential energy. Then it is moved 4 meters sideways and gains _____.
no potential energy
A feather and a coin are dropped in the AIR. Each falls with equal _____. -acceleration -kinetic energies -potential energies -none of the above
none of the above
If an object has kinetic energy, then it also must have _____.
speed
Two identical arrows, one with twice the KINETIC ENERGY of the other, are fired into a hay bale. The higher energy arrow will penetrate _____.
twice as far as the slower arrow
When an object is lifted 10 meters, it gains a certain amount of potential energy. If the same object is lifted 20 meters, its potential energy is ______.
twice as much
Car A has a mass of 1000 kg and a speed of 60 km/h, and car B has a mass of 2000 kg and a speed of 30 km/h. The kinetic energy of car A is _____.
twice that of car B
When a bullet is fired from a rifle, the force on the rifle is equal to the force on the bullet. However, the energy of the bullet is greater than the energy of the recoiling rifle because the _______.
force on the bullet acts for a longer distance
A ball is projected into the air with 100 J of kinetic energy which is transformed to gravitational potential energy at the top of its trajectory. When it returns to its original level after encountering air resistance, its kinetic energy is _____.
less than 100J
