# powers in ac circuits watch

1. a 100uf capacitor and a 8 ohms resistor are connected in series, the supply is AC, the frequency is 100Hz. a current of 8 amps (RMS) flows in the circuit. Determine :
(a) active power in the circuit,
(b) reactive power
(c) apartment power

this is how I was planning on solving this problem:
1. get total impedance of the circuit
2. get voltage of the circuit using the impedance and current .
3. get active power by using VIcos(°)

is my approach correct?
2. (Original post by Kmachakanja1)
a 100uf capacitor and a 8 ohms resistor are connected in series, the supply is AC, the frequency is 100Hz. a current of 8 amps (RMS) flows in the circuit. Determine :
(a) active power in the circuit,
(b) reactive power
(c) apartment power

this is how I was planning on solving this problem:
1. get total impedance of the circuit
2. get voltage of the circuit using the impedance and current .
3. get active power by using VIcos(°)

is my approach correct?
You need to use the appropriate formulas for apparent power, reactive power as well as active power. You have been given all the required values necessary to calculate things like voltage etc.

I can't remember exactly it's been a little while but I believe for some of those equations you'll need to use peak values not RMS values.

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Updated: November 4, 2017
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