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
2 answers
Power is proportional to the square of voltage. What number is sqrt2 times 3.5 V ?
4.9
3.5*square root of 2
3.5*square root of 2