Q5 of 51 Page 330

The peak power consumed by a resistive coil when connected to an AC source is 80W. Find the energy consumed by the coil in 100 seconds which is many times larger than the time period of the source.

Given that: Peak power ( = 80 W

Then, instantaneous power is



The energy consumed by the coil in time t=100 seconds will be


= P × t = 40 × 100


= 4000J


Energy consumed = 4.0KJ


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