What happened in the atomic epoch? When was it?
What will be an ideal response?
Neutral atoms of hydrogen and helium formed, and the universe shifted from radiation to matter domination. It lasted from about 400,000 years to around 100 million years.
You might also like to view...
Compared with the spectral lines in the solar spectrum, lines in a supergiant star's spectrum are
a. more narrow. b. broader. c. weaker. d. stronger. e. b & c
If a flea can jump up to 45 cm above its initial resting point, with what speed is it able to leave the ground when jumping?
A. 2.1 m/s B. 3.0 m/s C. 8.8 m/s D. 4.2 m/s
Dust particles are pulverized rock, which has density 2500 kg/m3. They are approximately spheres 20 ?m in diameter
Treating dust as an ideal gas, what is the root-mean-square speed (thermal speed) of a dust particle at 400°C? (The Boltzmann constant is 1.38 × 10-23 J/K.) A) 5.2 × 10-5 m/s B) 1.7 × 10-5 m/s C) 3.0 × 10-5 m/s D) 7.3 × 10-5 m/s
Cathode rays are
A. x-rays.
B. 
-rays.
C. electrons.
D. protons.
E. neutrons.