Question

The graph given here shows the frequency of sounds emitted by a source for 30 seconds. How many seconds of sound a normal human being be able to hear?

• A. 10 sec
• B. 20 sec
• C. 30 sec
• D. 05 sec

Answer 1

Answer: (B)

20 sec

The audible frequency range for human ear is from $20Hz$ to $20\times {10}^{3}Hz$ , in the given graph sound remains in this range from $5s$ to $25s$ i.e. for $20s$ .