The potential difference across a `150 mH` inductor as a function of time is shown in figure. Assume that the initial value of the current in the inductor is zero. What is the current when `t=2.0 ms`? and `t = 4.0 ms` ?

Answer

A, B

Explanation

`V_L=L(di)/(dt)`
`:. di=1/L(V_Ldt)`
`:. int di=i=1/LV_Ldt`
or `i=1/L` (area under `V_L` versus `t` graph)
a. At `t=2ms`
`i=(150xx10^-3)^-1(1/2xx2xx10^-3xx5)`
`=33.3xx10^-2A`
b. At `t=4ms`
Area is just double. Hence, current is also double.