Qstnid -I-2-the Voltage And Current In A Series Ac Circuit Are Given By V = V<sub>0</sub>cos Ωt And I = I<sub>0</sub> Sin Ωt. What Is The Power Dissipated In The Circuit? - 39: Alternating Current - Cbse-xi-physics

Home Learn Fast select Course

Show Unit/Chapter Change Unit Change Subject Last Menu

CBSE-XI-Physics

39: Alternating Current

with Solutions -

Qstn# i-2 Prvs-Qstn Next-Qstn

#2
The voltage and current in a series AC circuit are given by V = V₀cos ωt and i = i₀ sin ωt. What is the power dissipated in the circuit?
Ans : Voltage, V = V₀cos ωt
Current, i = i₀ sin ωt or i = i₀ cos (ωt `` -`` `` \frac{\pi }{2}``)
Power dissipated in an AC circuit is given by,
`` P={I}_{rms}{V}_{rms}\,\mathrm{\,cos\,}\varphi ``,
where I_rms = rms value of current
V_rms= rms value of voltage
ϕ = phase difference between current and voltage
Here, ϕ = `` \pi ``/2
`` \Rightarrow \,\mathrm{\,cos\,}\varphi =\,\mathrm{\,cos\,}\frac{\,\mathrm{\,\pi \,}}{2}=0``
`` \therefore P={I}_{rms}{V}_{rms}\times 0=0``
Page No 328: