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

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

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

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

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

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

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

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) the substance that does not allow electricity to travel through it
D) a form of energy produced by vibrating objects

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