If a beam of light has a wavelength of 555 x 10^-9m than whats its frequency?

Question

I know the answer is 5.4054 x 10^14Hz. I need to know how to get it and I need you to show the work in detail. Please help me out. Thanks.

Answer 1

f * w = c

Frequency in Hertz times wavelength in meters equals the speed of light.

To solve for frequency.
f = c/w

To solve for wavelength
w = c/f

Answer 2

The speed of light is 3x10^8m/s.

The frequency is determined by dividing the speed by wavelength.

The wave length is given as 555x 10^-9 m.

First divide 10^8 by 10^-9.

We get 10^ (8 + 9) = 10^ (17).

Then divide 3/ 555.

We get 0. 005405.

Therefore the answer is 0. 005405 x 10^ 17Hz.

The decimal point can be moved at our will.

If we move the decimal point to the right by one place then the number 17 is reduced by one. Hence the answer is 0.05405 x 10^ 16 Hz.

If we move the decimal point to the right by three places then the number 17 is reduced by three. Hence the answer is 5.405 x 10^ 14 Hz.

If we move the decimal point to the right by six places then the number 17 is reduced by six. Hence the answer is 5405. 0 x 10^ 11 Hz.

Answer 3

n X lambda = C

c=speed of light, n= frequency, lambda = wavelenght.

c=3X10^8 m/sec.

n = C/lambda = (3X10^8)/(555X10^-9) = (3X10^8)/(5.55X10^-9) = (3/5.55)X10^17=0.54054X10^17
= 5.4054X10^16 Hz.

so, the answer you proposed is wrong. it will be right if the wavelength given is in centimeters, i.e. 555X10^-9 cm = 555X10^-7 m.

Then the answer would be equal to (3X10^8)/(5.55X10^-7) = (3/5.55)X10^15 = 0.54054X10^15 = 5.4054X10^14 Hz.

I think now its clear to you.