Blackbody radiation is caused by an object's ____.
a. chemical structure
b. binding energy
c. excitation level
d. absolute zero
e. thermal agitation
Question 2Supermassive black holes have weaker gravity than stellar-mass black holes, producing slower spins for the infalling matter.
a. True
b. False
Indicate whether the statement is true or false
Question 3Electromagnetic waves are generated whenever the ____.
a. motion of any particle is changed
b. motion of any charged particle changes
c. motion of a positively charged particle is changed
d. motion of a negatively charged particle is changed
e. acceleration of any charged particle is changed
Question 4Normal galaxies in the present never went through an active galaxy phase.
a. True
b. False
Indicate whether the statement is true or false
Question 5The type of elements present in a gas can be determined by studying the ____.
a. number of ionized atoms in the gas
b. energy of the electrons being emitted by the gas
c. number of photons being absorbed or emitted by the gas
d. wavelengths of photons absorbed or emitted from the gas
e. number of excited atoms in the gas