Calculate the energy of a photon having a wavelength in thefollowing ranges.
(a) microwave, with λ = 50.00 cm
ev
(b) visible, with λ = 500 nm
ev
(c) x-ray, with λ = 0.50 nm
ev

The energy of a photon is given by the following formula:

(1)

Where:

is the Planck constant

is the frequency

Now, the frequency has an inverse relation with the wavelength :

(2)

Where is the speed of light in vacuum

Substituting (2) in (1):

(3)

Knowing this, let's begin with the answers:

For

For

For

As we can see, as the wavelength decreases, the energy increases.

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.