Vision Problems: A nearsighted person has a far point that is 4.2 m from his eyes. What power contact lenses must he wear to allow him to focus on distant mountains?
A. 0.48 diopters
B. -0.48 diopters
C. -0.36 diopters
D. -0.24 diopters
E. 0.24 diopters
Answer: D
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Polaroid sunglasses reduce much glare by polarization axes that are
A) vertical. B) horizontal. C) at right angles to each other.
Find the pressure in atmospheres in the water at the base of Dworshak Dam if the water in the reservoir is 200 meters deep. (1.01 × 105 N/m2 = 1 atm.)
A. 20.4 atm B. 24.7 atm C. 29.4 atm D. 194 atm E. 75 atm
In a series LRC circuit, the frequency at which the circuit is at resonance is f0. If you double the resistance, the inductance, the capacitance, and the voltage amplitude of the ac source, what is the new resonance frequency?
A) f0 B) f0/4 C) 2 f0 D) f0/2 E) 4 f0
Suppose that an atom has two energy levels separated by an energy difference ?E. When such atoms are in thermal contact with a reservoir at temperature T, there is roughly 1 atom in the higher state for every 4 in the lower state. What is the approximate ratio of ?E to kBT?
A. 
B. 4
C. ln 4
D. ?ln 4
E. e?1/4
F. e?4
T. Other (specify)