Question

A wave emitted from a source has a frequency of 10 Hz and wavelength 2.5 m. How much time will it take to reach a person located 5 m from the source?

Answer 1

The wave takes 0.2 seconds to reach a person located 5 m from the source.

Step-by-step explanation:

Let the frequency be 'f' and the wavelength be 'λ'

The frequency and wavelength relation is given by,

f = C/ λ

Here C is the speed of the wave.

10 = C/ 2.5

C= 10 x 2.5

C = 25 m/s

The relation between speed, time and distance is given by,

Speed = distance/ time

Here the distance we take will be 5m as we should find the time to reach the person 5m away from the source.

25 = 5 / t

t = 5/25

t = 0.2 seconds

The wave need 0.2 seconds to reach a person 5m away from the source.

Answer 2

Time taken to reach a person located 5m from the source is 0.2s

Step-by-step explanation:

Given:

Frequency, f = 10Hz

Wavelength, λ = 2.5m

Distance, d = 5m

Time, t = ?

We know:

velocity = f X λ

v = 10 X 2.5

v = 25 m/s

We know:

Distance = speed X time

On substituting the value we get:

5 = 25 X t

t = 0.2 seconds

Therefore, time taken to reach a person located 5m from the source is 0.2s