A source of unknown frequency gives 4 beats/s when sounded with a source of known frquency 250 Hz. The second harmonic of the source of unknown frequency gives five beats per second, when sounded with a source of frequency 513 Hz. The unknown frequency is

If we study the vibration of a pipe open at both ends. then the following statement is not true.

A wave travelling in the + ve x-direction having displacement along y-direction as 1 m, wavelength 2$$\pi $$ m and frequency of $${1 \over \pi }$$ Hz is represented by

The equation of a simple harmonic wave is given by

y = 3 sin$${\pi \over 2}$$(50t $$-$$ x),

where x and y are in metres and t is in seconds. The ratio of maximum particle velocity to the wave velocity is