An average induced emf of 0.20 V appears in a coil when the current in it is changed from 5 A in one direction to 5A in the opposite direction in 0.20 sec. Find the self induction of the coil.

Question

An average induced emf of 0.20 V appears in a coil when the current in it is changed from 5 A in one direction to 5A in the opposite direction in 0.20 sec. Find the self induction of the coil. (A) 4 × 10-3 H (B) 2 × 10-3 H (C) 2 √2 × 10-3 H (D) 3 √3 × 10-1 H

Tardigrade Admin · Accepted Answer

As we know, e=L (d I/d t) ⇒ 0.20 =(L(5-(-5))/0.20) (0.20 × 0.20/5+5)= L ⇒ 4 × 10-3 H

Q. An average induced emf of $0.20 V$ appears in a coil when the current in it is changed from $5 A$ in one direction to $5 A$ in the opposite direction in $0.20$ sec. Find the self induction of the coil.

$4 \times 1 0^{- 3} H$

$2 \times 1 0^{- 3} H$

$22 \times 1 0^{- 3} H$

$33 \times 1 0^{- 1} H$

As we know,
$e = L \frac{d I}{d t} \Rightarrow 0.20$
$= \frac{L ( 5 - ( - 5 ))}{0.20}$
$\frac{0.20 \times 0.20}{5 + 5} = L$
$\Rightarrow 4 \times 1 0^{- 3} H$

Q. An average induced emf of 0.20V appears in a coil when the current in it is changed from 5A in one direction to 5A in the opposite direction in 0.20 sec. Find the self induction of the coil.

4×10−3H

2×10−3H

22​×10−3H

33​×10−1H