

InterviewSolution
Saved Bookmarks
1. |
Show that average heat produced during a cycle of `AC` is same as produced by `DC` with `i=i_("rms")`. |
Answer» For an `AC,i=i_0sinomegat` Therefore, instantaneous value of heat produced in time `dt` across a resistance `R` is `:. dH-i^2Rdt=i_0^2Rsin^2omegatdt` `:.` Averge value of the produced during as cycle, `H_(av) =(int_0^TdH)/(int_0^Tdt)=(int_0^(2pi/omega)(i_0^2Rsin^2omegat)dt)/(int_0^(2pi//omega)dt)` `i_0^2/2R((2pi)/omega)=i_(rms)i^2RT` i.e. `AC` produces same heating efects as `DC` of value `i=i_(rms)` |
|