if a computer uses 150 watts, how much current does it draw if the household voltage is 115 volts. show your work including the formula that you started with
at least give me the formula
2007-11-29 02:51:53 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
For simple resistive loads
Watts = Volts X Amps
A computer power supply is not a simple resistive load, but it is close enough for these purposes. So you wuld say
150 = 115 X Amps
Amps = 150/115 = 1.3
The actual answer is probably closer to 1.5 amps
By the way, for AC, the voltage needs to be RMS voltage. Fortunately that's the number that you have.
2007-11-29 02:58:44 · answer #1 · answered by dogsafire 7 · 1⤊ 0⤋
Power (in Watts) is the product of voltage (in volts) and current (in amperes).
P = V*I
150 Watts = 115 Volts * I
I = 150 W/(115 V)
2007-11-29 03:01:20 · answer #2 · answered by Scott H 6 · 0⤊ 0⤋
power = voltage * current
However, for an AC circuit, the voltage fluctuates and I think a "root mean average" has to be taken. This is 1/SQRT(2).
150 watts = 115 Volts * current * 1/SQRT(2)
150 * SQRT(2) / 115 = 1.84 Amps
2007-11-29 03:01:40 · answer #3 · answered by Roger S 7 · 0⤊ 0⤋