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Question
The 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.
Solution
Peak power of the resistive coil, `P_0 = 80W `
Time, t = 100 s
RMS value of power `(P_{rms})` is given by,
`P_{rms = P_0/2}`
where P0 = Peak value of power
`therefore P_{rms} = P_0/2 = 40 W`
Energy consumed (E) is given by,
is given by,
E = Prms × t
= 40 × 100
= 4000 J = 4.0 kJ
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