NEET-XII-Physics
39: Alternating Current
- #5The peak power consumed by a resistive coil, when connected to an AC source, is 80 W. Find the energy consumed by the coil in 100 seconds, which is many times larger than the time period of the source.Ans : Peak power of the resistive coil, `` {P}_{0}=80\,\mathrm{\,W\,}``
Time, t = 100 s
RMS value of power `` \left({P}_{rms}\right)`` is given by,
`` {P}_{\,\mathrm{\,rms\,}}=\frac{{P}_{0}}{2}``,
where P0 = Peak value of power
`` \therefore {P}_{\,\mathrm{\,rms\,}}=\frac{{P}_{0}}{2}=40\,\mathrm{\,W\,}``
Energy consumed `` \left(E\right)`` is given by,
E = Prms × t
= 40 × 100
= 4000 J = 4.0 kJ
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