Emission nebulae are also called ________ because they are composed of ionized hydrogen
a. HI regions
b. HII regions
c. Bok globules
d. HeI regions
e. reflection nebulae
b
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Terminal Voltage and Internal Resistance: A circuit contains two batteries and a 2.0-? resistor as shown in the figure. The emfs and internal resistances of these batteries are indicated in the figure, and all numbers are accurate to two significant figures. What are the terminal voltages of (a) the 6.0-V battery and (b) the 12-V battery?
What will be an ideal response?
Simple Harmonic Motion: If the angular frequency of the motion of a simple harmonic oscillator is doubled, by what factor does the maximum acceleration of the oscillator change?
A. 2 B. 4 C. It does not change. D. 1/2 E. 1/4
The theory of general relativity proves that wormholes like those used in science fiction cannot exist
Indicate whether the statement is true or false
Rocks are classified into three types on the basis of their
a. process of formation. b. age. c. geographic origin. d. color.