A source of sound gives five beats per second, when sounded with another source of frequency `100 s^(-1)`. The second harmonic of the source, together with a source of frequency `205 s^(-1)` gives five beats per second. What is the frequency of the source ?

Options

A. `105 s^(-1)`
B. 205 `s^(-1)`
C. 95 `s^(-1)`
D. 100 `s^(-1)` .

Answer

A, C

Explanation

The freq. of the source is `(100 pm 5) ` i.e., 105 or 95 Hz. The second harmonic is 210 or 190 . As is gives 5 beats / sec with 205 , therefore, its freq. is 105 and harmonic 210 .
correct choice is (a).
correct choice is (c).