Question

What is the color and wavelength of light with 2.88 x 10-19 J of energy?

Answer 1

Answer : The color and wavelength of light is red and
`6.9* 10^(-7)m` respectively.

Explanation :

Given:

Energy =
`2.88* 10^(-18)J`

Now we have to determine the wavelength of light.

Formula used:

`E=(hc)/(\lambda)`

where,

E = energy

h = Planck's constant =
`6.626* 10^(-34)J.s`

c = speed of light =
`3* 10^8m/s`

`\lambda` = wavelength of light

Now putting all the given values in this formula, we get:

`2.88* 10^(-18)J=((6.626* 10^(-34)J.s)* (3* 10^8m/s))/(\lambda)`

`\lambda=6.9* 10^(-7)m`

From the electromagnetic spectrum we conclude that the color of the light will be red of wavelength
`6.9* 10^(-7)m`.

Therefore, the color and wavelength of light is red and
`6.9* 10^(-7)m` respectively.