The change in a pitch of a sound as an object moves closer or farther away is a result of​

The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener. As the source of sound waves approaches a listener, the sound waves get closer together, increasing their frequency and the pitch of the sound.

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Friction is the force that act and opposes all motion of moving objects