Physical Science Ch. 4 Review

The ability to do work is

• energy

• force

• machines

• work

A machine that does work with only one movement of the machine and changes the size or direction of a force is a(n)

• simple machine

• compound machine

• effort machine

• screw

The kinetic energy of an object increases as its ___________ increases

• gravitational potential energy

• potential energy

• specific heat

• velocity

Increasing the speed of an object _________ its potential energy

• does not affect

• increases

• decreases

• changes

The SI unit for energy is the _______________.

• calorie

• joule

• meter per second

• kilogram

Which of the following devices does not make use of electrical energy?

• upright piano

• radio

• toaster

• digital camera

A bus engine transfers chemical potential energy into ______ so that the bus moves

• thermal energy

• gravitational potential energy

• electrical energy

• kinetic energy

In a nuclear fusion reaction, mass is transformed into

• matter

• nuclei

• energy

• light

According to the law of conservation of energy, the total amount of energy in the universe

• remains constant

• changes constantly

• increases

• decreases

If a weight lifter is holding barbells above his head, what does he have to do to perform work?

• stand still

• move barbells sideways

• step forward

• lower barbells