Question

The microwave background radiation is observed at a wavelength of 1.9 millimeters. The red shift of these photons is observed to be raoughly 1100. What would be the emitted wavelength?

Answer 1

1730nm

Step-by-step explanation:

Observed wavelength λ= 1.9 millimeters

Red shift of photons = 1100

Emitted wavelength = λo

Red shift = λ - λo/ λo = 1100

= [(1.9x10^-3 - λo)/ λo] = 1100

= 1.9x10^-3 - λo = 1100 λo

= 1.9x10^-3 = 1100 λo + λo

= 1.9x10^-3 = 1101 λo

We divide through by 1101 to get the value of lambda

1.9x10^-3/1101 = λo

λo = 0.000001726

λo = 1726nm

This is approximately

λo = 1730nm

Thank you!