Question

A wave travels at speed 4.0 m/s. Its wavelength is 22 cm. What is the frequency of the wave?

A) 28 s^-1
B) 11 s^-1
C) 18 s^-1
D) 23 s^-1

Answer 1

c)
`18s^(-1)`

Step-by-step explanation:

The information we have is:

Speed:
`v=4m/s`

wavelength:
`\lambda = 22cm` we need to convert this quantity to meters:

`22cm=22/100m=0.22m`, so
`\lambda =0.22m`

------------------------------------------------

We need to find the frequency of the wave, for that we use the formula:

`v=f\lambda`

where
`f` is the frequency.

In tha last equation we clear for
`f`

`f=(v)/(\lambda )`

and we substitute the known values:

`f=(4m/s)/(0.22m)\\ f=18.18s^(-1)`

the answer is c)
`18s^(-1)`

Answer 2

Given data:

wave length (λ) = 22 cm = 0.22 m,

speed of wave length(v) = 4 m/s ,

determine the frequency (f) = ?

We know that ,

wave length and frequency of light are closely related. The higher the frequency, shorter is the wavelength and vice-versa.

Mathematically, λ = v/f -------------------- (i)

where, λ = wave length (m)

v = speed of wave length (m/s)

f = frequency (Hz)

From the equation (i) ,

frequency (f) = v/λ

= 4 / 0.22

= 18.18 /second

frequency (f) of the wave is 18 /sec or (18 Hz)

Note: frequency is defined as "number of occurrences per unit time", measured in Hz.