A coil has an inductance of 0.80 H and a resistance of 41 . The coil is connected to a 5.0 V ideal battery. (a) When the current reaches half its maximum value, at what rate is magnetic energy being stored in the inductor? (b) When the current reaches half its maximum value, at what rate is energy being dissipated? (c) When the current reaches half its maximum value, what is the total power that the battery supplies?
We first need the time at half maximum current. I (V/R)[1 - e^(-Rt/L)] Max current V/R so V/(2R) V/R[1 - e^(-Rt/L)] e^(-Rt/L) 0.5 -Rt/L ln(0.5) t -L.ln(0.5)/R -0.8 ln(0.5)/41 0.014 s Magnetic energy stored: E (1/2)LI^2 dE/dt LI dI/dt . dI/dt (V/L)e^(Rt/L) 3.05, t 0.014 dE/dt {( LV)/2R} x 3.05 0.15 Js^-1 Electrical power dissipated P I^2 R (V^2/4R^2)R 0.15 Js^-1 Power drawn from battery 0.15 + 0.15 0.3 W
Energy Stored In A Inductor
An inductor might no longer likely keep magnectic capability. It converts electric powered capability flowing with the aid of it to magnectic capability. If the electricity flow is stopped, the magnectic field colapses (like Jis4Jenius Jerald pronounced above). it extremely is termed an inductor using fact a changing magnetic field around the cord (or coil) induces electricity into it.
