Question

Radiation has been detected from space that is characteristic of an ideal radiator at T = 2.728 K. (This radiation is a relic of the Big Bang at the beginning of the universe.) For this temperature, at what wavelength does the Planck distribution peak? In what part of the electromagnetic spectrum is this wavelength?

Short answer

At the wavelength 1.06 mm, the Planck distribution peak.

This wavelength is located in the microwaves spectrum.

Step-by-step solution

Determine the wavelength

Use Wien displacement law to follow the wavelength

Substitute the values in the above formula to find the wavelength at the peak of the Planck distribution

The wavelength at the peak Planck’s distribution is 1.06 mm, thus, this wavelength is located in the microwave spectrum.