Giraffe uses ______ sounds for communication.

Which of the following parts of the ear transmits the electrical signals to the brain for interpretation?

• The optic nerves relay messages from your eyes to your brain to create visual images.
• Cochlea is the part of inner ear.
• Blood vessels deliver blood to the organs and tissues in your body.

Increase in wavelength ___________ frequency.

• Wave speed= frequency × wavelength.
• Frequency = wave speed/wavelength.

The frequency of vibration of an object is 25000 Hz. A person ____ hear it.

Frequency above 20KHz is called ultrasound.

Which of the following is not a part of the middle ear?

The frequency of vibration of an object is 150 Hz. A person ____ hear it.

The frequency of the sound can be modified to change the infrasound to _____.

When an ear drum encounters a rarefaction, it ____.

Compression or high pressure push the eardrum inwards.

When the air pressure near the ear drum increases, it ____.

Low pressure regions or rarefactions pull the eardrum outwards.

Ultrasound frequencies are ____ audible frequencies.

As we humans grow older, our ears become ______.

Elephants use _____ to communicate with each other.

• The infrasound frequencies are good for long distance communication because they travel well through objects instead of being reflected.

What does a hearing-impaired do to hear clearly?

When an ear drum encounters a sound it ____.

• Compression or high pressure pushes the eardrum inwards.
• Rarefaction or low pressure pulls the eardrum outwards.

The frequency of vibration of an object is 15000 Hz. A person ____ hear it.

Which of the following is a part of inner ear?

• Cochlea is an important organ for sound perception.