Two charged bodies separated by a distance d exert an electrical force on each other. The distance d is doubled. The electrical force on each body now
a. decreases by 1/4.
b. decreases by 1/2.
c. stays the same.
d. increases by 2 times.
e. increases by 4 times.
a
You might also like to view...
6The sideral period of the moon
a. is about 27.32 days long. b. is the period of time for the moon to orbit Earth once with respect to the stars. c. is the period of time between successive eclipses at a given location on Earth. d. is the period of time from when the moon rises until the moon rises again the next night. e. a and b above
Which of the following is always true about images captured with x-ray telescopes?
A) They are always shown with colors that are not the true colors of the objects that were photographed. B) They always are made with adaptive optics. C) They show us light with extremely long wavelengths compared to the wavelengths of visible light. D) They always have high angular resolution. E) They are always pretty.
Star A has twice the absolute temperature of star B, but they both have the same radius. What is the ratio of star A’s power output to star B’s output due to electromagnetic radiation? The emissivity of both stars can be assumed to be 1
1.4 2.8 3.16 4.64
Compound Microscope: You have a choice between two lenses of focal lengths fa and fb, where fb = 2fa, to use as the objective lens in building a compound microscope. If the magnification you obtain using lens a is Ma, what will be the magnification when using lens b?
A. Mb = 2 Ma B. Mb = 4 Ma C. Mb = 8 Ma D. Mb = Ma/4 E. Mb = Ma/2