Answer to Question #276652 in Electricity and Magnetism for Sophia

Question

An external voltage of 60 V is applied to a coil whose resistance is 5.25 Ω. What is the current in the coil if the back EMF is 9.85 Ω?

Answer 1

$ϵi=V_S−IR$

$I=-[\frac{ϵi-V_S}{R}]$

Where;

ϵi=back EMF=9.35V

$V_s$ =External voltage=60V

I= current=

R=resistance=5.25Ω

$I=-[\frac{9.85-60}{5.25}]=9.65A$

I=9.65A