Question

Enter your answer in the provided box.

How much more energy per photon is there in green light of wavelength 536 nm than in red light of wavelength

622 nm?

__× 10 __ J
(Enter your answer in scientific notation.)

Answer 1

Answer : The correct answer is
`5.20* 10^(-20)J`

Explanation :

For green light :

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

where,

E = energy of green light = ?

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

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

`\lambda` = wavelength of light = 536 nm =
`536* 10^(-9)m`

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

`E=((6.626* 10^(-34)Js)* (3* 10^(8)m/s))/(536* 10^(-9)m)`

`E=3.71* 10^(-19)J`

For red light :

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

where,

E = energy of red light = ?

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

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

`\lambda` = wavelength of light = 622 nm =
`622* 10^(-9)m`

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

`E=((6.626* 10^(-34)Js)* (3* 10^(8)m/s))/(622* 10^(-9)m)`

`E=3.19* 10^(-19)J`

Now we have to calculate the energy difference.

`\text{Energy difference}=E_(green)-E_(red)`

`\text{Energy difference}=3.71* 10^(-19)J-3.19* 10^(-19)J=5.20* 10^(-20)J`

Therefore, the correct answer is
`5.20* 10^(-20)J`