Q.

An alternating voltage V(t)=220 sin 100πt volt is applied to a purely resistive load of 50Ω. The time taken for the current to rise from half of the peak value to the peak value is                [2024]

1 5 ms  
2 3.3 ms  
3 7.2 ms  
4 2.2 ms  

Ans.

(2)

V(t)=220sin(100πt)

I=VsR=22050sin(100πt)

I=225sin(100πt)

cosθ=I02I0=12θ=60°=π3

Using phasor, t=π/3100π

t=1300 sec=103 msec

t=3.3 msec