Browse Questions

Effective value of current is $5.0\;amp$ in a 50 cycle ac circuit. What is value of current $\large\frac{1}{300}\;$seconds after it is zero ?

$(a)\;3.732\;amp \\(b)\;1.414\;amp \\ (c)\; 6.124\;amp \\ (d)\;5.123\;amp$

given $I_{rms}=5.0\;amp$
$I_0=\sqrt 2 Ims$
$f= 50 cycles /sec,\qquad t= \large\frac{1}{300} \;sec$
$I= I_0 \sin wt$
$\quad= \sqrt 2 \times 50 \sin 2 \pi \times 50 \times \large\frac{1}{300}$
$\quad= \sqrt 2 \times 50 \times \sin \large\frac{\pi}{3}$
$\quad= 6.124 \;amp$
Hence c is the correct answer.