Question

What is the speed of an electromagnetic wave with a frequency of 1.33x10^17Hz and a wavelength of 2.25nm?

Answer 1

Wavelength = 2.25nm = 2.25 x 10^(-9)m

Frequency = 1.33 x 10^17Hz

Speed = 2.25 x 10^(-9) x 1.33 x 10^17 = 2.99 x 10^8m/s

So the answer is: 2.99 x 10^8m/s

Answer 2

Answer : The speed of electromagnetic wave is
`2.99* 10^(8)m/s`

Explanation : Given,

Frequency of wave =
`1.33* 10^(17)Hz=1.33* 10^(17)s^(-1)`

Wavelength of wave =
`2.25nm=2.25* 10^(-9)m`

Formula used :

`\\u=(c)/(\lambda)`

where,

`\\u` = frequency of light

`\lambda` = wavelength of light

c = speed of electromagnetic wave = ?

Now put all the given values in the above formula, we get:

`1.33* 10^(17)s^(-1)=(c)/(2.25* 10^(-9)m)`

`c=(1.33* 10^(17)s^(-1))* (2.25* 10^(-9)m)`

`c=2.99* 10^(8)m/s`

Therefore, the speed of electromagnetic wave is
`2.99* 10^(8)m/s`