Final answer:
Noise is made of irregular and disorganized sounds, while pitch of a sound is related to frequency of vibrations. The Doppler effect is the observed change in frequency of a sound due to relative motion between the source and the observer. Correct Options are D followed by A.
Step-by-step explanation:
___ is made of sounds that are irregular and disorganized. The correct answer is d. Noise. Noise refers to sounds that are irregular, disorganized, and often considered to be unpleasant or undesirable. The pitch of a sound is most closely related to the a. frequency of vibrations. This means that high pitched sounds have a high frequency of vibration, and low pitched sounds have a low frequency of vibration.
The Doppler effect is a phenomenon that occurs when there is relative motion between a sound source and an observer. It results in a change in the observed frequency of the sound, known as a Doppler shift. This effect is most noticeable when a sound source moves towards or away from an observer, such as the shift in pitch heard from a passing siren or a train's warning bell as it moves past the observer.