Question

A sound wave is passing through the air. 1000 compressions and rarefactions are passing through a point in one second. Which of the following is the frequency of the sound wave?

• A. 1000 Hz
• B. 1000 J
• C. 1000 $s^{-1}$
• D. 2000 Hz

Answer 1

Answer: (A), (C)

The correct options are
A

1000 Hz

C

1000 $s^{-1}$

Frequency is the number of rare fractions or compressions passing through a fixed point in unit time (one second).

$Frequency=\frac{numberofwaves}{time}=\frac{1000}{1}=1000Hz$

Also, the frequency can be defined as the number of waves that can be produced in one second given the time taken to produce one wave i.e. Time period.

I.e Frequency ($\nu$) = $\frac{1}{timeperiod}$

S.I. unit of time is second (s).

threfore, $1Hz=1s^{-1}$

So, $1000Hz=1000s^{-1}$