The background microwave radiation,discovered in 1965 by Penzias and Wilson,has its peak intensity at a wavelength of 1.06 mm.What blackbody temperature does this wavelength imply for the universe? (σ = 5.670 × 10^-8 W/m² • K⁴,Wien displacement law constant is 2.90 × 10^-3 m • K) A) 2.7°C B) -270°C C) 0.0027 K D) 0.00°C E) -2.7°C

Question

Quizplus · Accepted Answer

According to Wien's displacement law, the peak wavelength λ_peak is related to the blackbody temperature T by:

λ_peak = b/T

where b is the Wien displacement constant. Substituting the given values for λ_peak and b, we have:

1.06 mm = (2.90 × 10^-3 m • K)/T

Solving for T, we get:

T = (2.90 × 10^-3 m • K)/(1.06 mm) = 2.73 K

Therefore, the blackbody temperature implied by the peak intensity of the background microwave radiation is 2.73 K. This corresponds to a temperature of -270°C, as K and °C are on the same scale but with different zero points. Thus, the best choice is B.

The Background Microwave Radiation,discovered in 1965 by Penzias and Wilson,has