As the Universe cooled, it eventually reached a temperature of 3,000 K and protons were able to capture and hold electrons to form neutral hydrogen. This process is known as
a. ionization.
b. isotropy.
c. annihilation.
d. recombination.
e. hydration.
d
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If a charge of -3 x 10-6 C were allowed to fall through a potential difference of +500 V, the change in potential energy for the charge would be
A. -1.5 × 10-3 Joules. B. 1.5 × 10-4 Joules. C. -1.5 × 10-4 Joules. D. 1.5 × 10-3 Joules.
__________ a physical state of being physiologically overwhelmed that is associated with a heart rate of over 100 bpm and oxygen concertation that falls below 95.
Fill in the blank(s) with the appropriate word(s).
Consider a situation where two moving objects collide, stick to each other, and move off together. For a body oscillating at the end of a spring, the energy is only elastic potential energy
Indicate whether the statement is true or false
The Andes and the Sierra Nevada Mountains began to form during the Mesozoic due to
A) the formation of the Atlantic Ocean. B) subduction of Pacific oceanic crust beneath North and South American continental crust. C) rifting between North America and Africa. D) meteorite bombardment in Mexico.