- #1
Prashasti
- 63
- 2
Hello!
A sinusoidal voltage of peak 283 V and frequency 50 Hz is applied to a series LCR circuit in when R = 3ohm, L is 25.48mH and C is 796 microF. Find the power dissipated in the circuit.
The book says,
Power = I^2 R
Where I = rms current.
Now, I = 283/5 [itex]\sqrt{2}[/itex] = 40 A
So, power = 40×40×3 = 4800 W.
Why didn't they include 'the power factor' while calculating the power?
Also, isn't what they have calculated is a special case? I mean they've taken Z = R, ( because power = I^2 Z cos θ) which is only possible at resonance. (Cosθ = power factor, which they have taken as 1)
This can't be a general solution, right?
Homework Statement
A sinusoidal voltage of peak 283 V and frequency 50 Hz is applied to a series LCR circuit in when R = 3ohm, L is 25.48mH and C is 796 microF. Find the power dissipated in the circuit.
The book says,
Power = I^2 R
Where I = rms current.
Now, I = 283/5 [itex]\sqrt{2}[/itex] = 40 A
So, power = 40×40×3 = 4800 W.
Why didn't they include 'the power factor' while calculating the power?
Also, isn't what they have calculated is a special case? I mean they've taken Z = R, ( because power = I^2 Z cos θ) which is only possible at resonance. (Cosθ = power factor, which they have taken as 1)
This can't be a general solution, right?