
The temperature of the cosmic microwave background (CMB) varies with time. If the peak of the...
The peak wavelength in the cosmic microwave background is 1mm. This corresponds to a temperature of about 3K. To what frequency would you need to tune a radio receiver to receive a microwave signal with this wavelength
if a photon from the cosmic microwave background had wavelength λ0 when it was emitted at redshift z, its wavelength today is λ= λ0 (1+z). (a) let T be the symbol for the temperature of the cosmic microwave background today. explain why the radiation temperature was T0= T(1+z) at redshift z (b) what was the radiation temperature at z= 1? (c) at what redshift was the radiation temperature equal to 293 K (a typical room temperature)
10 marks] Question 10 [2 2 2 2 2 The Cosmic Microwave Background (CMB) is blackbody radiation remaining from an hot phase in the universe, and currently has a temperature of 2.7K. First we will determine the current number density of CMB photons. early (a) What is the current energy density of the CMB? (b) What is the average energy of a single photon in the CMB today (at the peak of the blackbody curve)? (c) If we take this...
The temperature of the cosmic background radiation is measured to be 2.7 K. What is the wavelength of the peak in the spectral distribution at this temperature? What frequency corresponds to this wavelength?
1. [Cosmic background temperature] At present, the cosmic background radiation is at 3 K. Suppose the universe expands adiabatically (but not necessarily quasistatically). What can you say about the tem- perature of the cosmic background radiation when the total volume of the universe was one half of the present volume?
1. [Cosmic background temperature] At present, the cosmic background radiation is at 3 K. Suppose the universe expands adiabatically (but not necessarily quasistatically). What can you say about the tem-...
The cosmic background radiation permeating the universe has the spectrum of a 2.7-K blackbody radiator. What is the peak wavelength of this radiation? The constant in Wien's law is 0.0029 m ∙ K. Hint: the answer will be in mm
3. Calculate the blackbody temperatures (K) from the peak wavelengths given in a) through b), and the peak wavelength (m) from the temperatures given in c) through d): a. 180 nm (surface of hot star) b. 2.4 microns (surface of cold star) c. 60 K (interstellar cloud) d. 3 K cosmic microwave background radiation left over from the Big Bang
Cosmic background radiation. The following figure shows measurements of the energy density of the background cosmic radiation. The graphical quantity is the spectral density as a function of the energy per unit volume according to the relationship: di / dw = cu(w) / 41 Assuming Planck's Law, estimate the temperature of the background cosmic radiation. Use that lerg = 10-7 J, kg = 1.38 x 10-23 J/K y c~ 10%m/s. -3.00 30 Wavelength (cm) 0.3 0.03 10-14 10-15 10-16 10-17...
Please make sure you give me the correct answer
13) The cosmic background radiation permeating the universe has the spectrum of a 2.7-K blackbody radiator. The energy density of deep space is 4.19 x 10-8 J/cm3 a, What is the peak wavelength of this radiation? b, Assuming the energy density of space is from these photons, how many photons are there on average in each cubic centimeter of space?
Suppose a star with radius 8.44 x 10^8 m has a peak wavelength of 677 nm in the spectrum of its emitted radiation. (a) Find the energy of a photon with this wavelength. J/photon (b) What is the surface temperature of the star? K (c) At what rate is energy emitted from the star in the form of radiation? Assume the star is a blackbody (e = 1). W (d) Using the answer to part (a), estimate the rate at...