A) liquid
B) light
C) energy
D) motion

A) vibrating objects
B) energy changing form
C) changes in the state of matter
D) thinking about objects

A) water
B) empty space
C) solid objects
D) matter

A) gels
B) solids
C) liquids
D) gases

A) a block of iron
B) a mixture of gases
C) a pool of water
D) empty space

A) circular motions
B) straight lines
C) empty space
D) waves

A) see
B) speak
C) hear
D) feel

A) false
B) true

A) the amount of matter in an object
B) a form of energy that travels in waves and can move in empty space
C) a form of energy produced by vibrating objects
D) the substance that does not allow electricity to travel through it

A) a form of energy produced by vibrating objects
B) the measure of the amount of gravity acting on an object's mass
C) a force that works against motion
D) move back and forth rapidly