The magnetic flux (in weber) linked with a coil of resistance `10 Omega` is varying with respect to time t `phi = 4t^(2) + 2t + 1`. Then the current in the coil at time t = 1 second is

Options

A. 0.5A
B. 2A
C. 1.5A
D. 1A

Answer

D

Explanation

Given : `phi = 4t^(2)+2t+1 wb`
`therefore (d phi)/(dt)=(d)/(dt)(4t^(2)+2t+1)=8t+2=|epsilon|`
Induced current, `I=(|epsilon|)/(R )=(8t+2)/(10Omega)=(8t+2)/(10)A`
At `t=1 s, I=(8xx1+2)/(10)A=1A`