Answer: person C.
Explanation:
1) The frequency of the sound wave is perceived or detected as the pitch of the sound.
And the higher the frequency the the higher the pitch.
2) When a sound source is in motion there is an apparent change in the pitch perceived. This is the Doppler effect, which is defined as the change in the perception of the pitch in virtue of the relative motion between the listener and the emitter of the sound.
If the source of the sound is moving toward the listener, the pitch will be higher that if the sound is at rest. If the source of the sound is moving away from the listener, the pitch will be lower.
That is because the the motion of the emitter increases (or decreases, depending on whether the emitter is moving toward or away the listener) the speed of the sound waves and they arrive more frequently (or less frequently).
Then, since the sound is emitted by the motorbike and it is moving toward the person C, he will hear the highest pitch.
Answer: The wheel's average rotational acceleration is -0.4 radians per second squared (rad/s^2)
Explanation: Please see the attachments below
Answer:
I'm learning physics too, mabye we can learn together. by the way, the are 2 very good apps with physics : "khan academy" and "crash course"
To calculate the distance to a star, astronomers observe it from different places along Earth's orbit around the Sun. If they measure the object's position several months apart, their "two eyes" will have a separation of well over 100 million miles!
