7. What is the relationship of temperature to the speed of sound?
A. equal
B. no relationship
C. directly proportional
D. inversely proportional
8. Sound travels through warm materials than cold materials because ______.
A. warm particles move slowly
B. gas particles are packed tightly
C. warm particles are moving quickly
D. sound does not travel through a warm substance
9. Ships use echolocation to measure the ______.
A. size of fish
B. area of ocean
C. depth of water
D. density of water
10. When the direction of a wave changes as it passes from one medium to another, it is called ___.
A. density
B. echo
C. reflection
D. refraction
11. What happens to the speed of sound when it travels in warmer objects?
A. constant
B. faster
C. slower
D. cannot be determined
12. When a boy yells his name inside a cave, the sound reflects off the walls of the cave and travels back to his ears. What do you call the reflected sound?
A. density
B. echo
C. echolocation
D. refraction ​