Question

A coil has an inductance of 5 H and a resistance of 20 Ω. If a DC voltage of 100 V is applied to the coil, find the energy stored in the coil when a steady maximum current has been reached

Answer 1

Answer:62.5 J

Step-by-step explanation:

Given

Inductance(L)=5 H

resistance(R)
`=20 \Omega`

Voltage(V)=100 V

`Current=(100)/(20)=5 A`

Current in L-R circuit is given by

`I=I_0\left [ 1-e^{-(Rt)/(L)}\right ]`

and Power=i^2R+Li\frac{di}{dt}[/tex]

For Steady state i.e. at
`t=\infty`

`I=I_0`

Energy Stored is
`E=(Li^2)/(2)`

`E=(5* 5^2)/(2)=62.5 J`