Sound Energy

When a sound wave hits the eardrum, what happens to the eardrum to allow the transmission of the sound to the inner ear?

• it vibrates 
• it ruptures
• it fills with liquid
• `it remains motionless

In the inner ear, vibrations created by sound are changed into electrical signals so that

• the brain can interpret the vibrations
• the hair cells inside the cochlea can blend
• the outer ear can capture sound
• the eardrum can vibrate

Research ships use sound waves to find objects underwater. What happens to the sound waves when they are emitted from the ship?

• THey are absorbed by the water around the ship
• They are reflected off objects they strike in the water
• They are absorbed by the air above the ship
• They are regracted by objects they strike in the water

How does cupping your hand around your ear help you hear?

• Sound waves move through the hand into the ear
• sound waves have more air to move through to get to the ear
• more sound waves are regracted into the ear
• The hand reflects more sound waves into the ear

Even though bats cannot see well, sonar allows them to fly in and out of tight spaces, even at night.  Sonar is a phenomenon of sound that relies on 

• refracted sound
• absorption of sound
• echoes 
• reflected light

What is an echo? 

• a sound absorbed by  materials around it.
• a sound traveling to a listener far away
• a sound changing in frequency
• a sound that repeats, caused by reflection of sound waves

If you want to reduce the amount of echoing in a room, which is the best materiel to use on the walls?

• Brick
• cork
• Wood
• metal

In which medium will sound travel the fastest?

• air
• water
• glass
• salt water

In which medium will sound travel slowest?

• air
• water
• glass
• salt water

Sound travels fastest through a 

• vacuum
• gas
• solid
• liquid