# PHYSICS

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A stereo amplifier creates a 3.5 V potential difference across a speaker.

To double the power output of the speaker, the amplifier's potential difference must be increased to:

A. 7.0 V
B. 9.9 V
C. 12 V
D. 4.9 V

• PHYSICS -

Power is proportional to the square of voltage. What number is sqrt2 times 3.5 V ?

• PHYSICS -

4.9

3.5*square root of 2

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