Question

In which of the following, two sounds of same loudness and same pitch produced by two different instruments differ?
${\text{A}}{\text{.}}$ Amplitudes
${\text{B}}{\text{.}}$ Frequencies
${\text{C}}{\text{.}}$ Waveforms
${\text{D}}{\text{.}}$ All of the above

Answer 1

Hint: Here, we will proceed by defining the various properties of any wave like amplitude and frequency of the wave. Then, we will define the term waveforms in waves topic. Finally, we will write down the parameter which depends upon the source.

Complete Step-by-Step solution:
Amplitude is basically one of the properties of a wave. The amplitude of a wave refers to the maximum quantity of a particle being displaced from its position of rest on the medium. The amplitude is, in a way, the gap from rest position to crest position. Similarly, the amplitude can be determined from the position of the rest to the position of the trough. The amplitude may be determined as the length of a line segment that is perpendicular to the position of rest and stretches vertically upwards from the location of rest to the location of the crest or the location of the trough.
Wave frequency is the number of waves which pass a fixed point in a given amount of time. Wave frequency can be calculated by counting the number of wave crests (high points) that reach the fixed point within 1 second or any other period of time. The higher the number, the more frequency the waves will have. The SI unit of wave frequency is referred to as hertz (Hz), where 1 hertz is equal to 1 wave which passes a fixed point within 1 second.
A waveform defines a wave by graphing how a particle of air is displaced with time. Such waveforms are said to be periodic, since a constant tone can be generated by repeating the wave they reflect. The more the wave repeats, the greater the sound's pitch.
Amplitude also translates into loudness for the human ear and hence results in increasing the amplitude of a sound which will increase how loud it will seem to us.
The waveforms depend, along with the principal note, on the number of the subsidiary notes and their relative amplitude. Then the waveform of the sound is obtained through the resultant or net vibration which occurs by the superposition of multiple vibrations available.
Therefore, two sounds of same loudness and same pitch produced by two different instruments will differ in their waveforms.

Hence, option C is correct.

Note- For this particular problem, it is important to note that the various waveforms have contrasting harmonics. A harmonic is an additional frequency which the wave produces. The sine waveform is peculiar in that it has no extra harmonics and it is referred to as the fundamental waveform.