A 100 W lightbulb has an energy efficiency of 5%. It is turned on for one minute. During this time, the visible radiant energy output of the lightbulb is
A) 300 J.
B) 6000 J.
C) 5700 J.
D) impossible to determine because we don't know the voltage.
E) impossible to determine because we don't know the power.
A
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A) is always zero. B) remains a non-zero constant. C) continuously increases. D) continuously decreases. E) first decreases and then increases.
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