NEET Physics Question - Waves - Waves and its Characteristics

Assertion (A): If two sounds of frequencies 256 Hz and 260 Hz reach our ear simultaneously then we hear a sound of frequency 258 Hz.

Reason (R): We hear a striking variation in the intensity of sound that repeat at a frequency of 4 Hz.

Both (A) & (R) are true and the (R) is the correct explanation of the (A)

Both (A) & (R) are true but the (R) is not the correct explanation of the (A)

(A) is true but (R) is false

Both (A) and (R) are false

Solution:

When two sound waves of frequencies (f_1) and (f_2) interfere, the perceived average frequency is \((f_1 + f_2)/2 = (256 + 260)/2 = 258 \text{ Hz}\). So (A) is true. The beat frequency is \(|f_1 - f_2| = |256 - 260| = 4 \text{ Hz}\).

So (R) is also true. However, the beat phenomenon does not explain the average perceived frequency.

Rankers Physics

Sound Beats and Frequency

Solution:

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