Question

If you're standing near the track at an indy car race, one of the most exciting things is watching and listening to the cars go by. It can get you excited to be at a race even if the race itself is boring.

As the cars approach and then get farther away, the pitch of the sound of their engines changes. How would you summarize the way the pitch of the engines changes as the cars approach and then start to move further away from you?

Choose the two that are closest to correct

As the cars get closer, the pitch of the engines increases, based on how fast they're moving.

As the cars get closer, the pitch of the engines decreases, based on how fast they're moving.

As the cars get further away, the pitch of the engines increases, based on how fast they're moving.

As the cars get further away, the pitch of the engines decreases, based on how fast they're moving.

Answer 1

Answers :

• As the cars get closer, the pitch of the engines increases, based on how fast they're moving.
• As the cars get further away, the pitch of the engines decreases, based on how fast they're moving.

According to Doppler effect : When a car approaches you, the sound waves that reach you have a shorter wavelength and a higher frequency. You hear a sound with a higher pitch. When the car moves away from you, the sound waves that reach you have a longer wavelength and lower frequency. You hear a sound with a lower pitch.