The current passing through an inductor coil of 5H is decreasing at the rate of 2A/s, the emf developed across the coil is

Question

The current passing through an inductor coil of 5H is decreasing at the rate of 2A/s, the emf developed across the coil is (A)  +10.0V  (B)  -10.0V  (C)  +2.5V  (D)  -2.5V

Tardigrade Admin · Accepted Answer

If on changing current through the coil, the emf induced in the coil ise, then by Faradays 2nd law, we have

e = - L \frac{Δ i}{Δ t}

where,

\frac{Δ i}{Δ t}

is rate of change of current.
Given,

L = 5 H, \frac{Δ i}{Δ t} = - 2 A / s

(decreasing)

∴

e = - 5 \times (- 2) = + 10 V

Q. The current passing through an inductor coil of 5H is decreasing at the rate of 2A/s, the emf developed across the coil is

$+ 10.0 V$

$- 10.0 V$

$+ 2.5 V$

$- 2.5 V$

If on changing current through the coil, the emf induced in the coil ise, then by Faradays 2nd law, we have
$e = - L \frac{Δ i}{Δ t}$
where, $\frac{Δ i}{Δ t}$ is rate of change of current.
Given, $L = 5 H, \frac{Δ i}{Δ t} = - 2 A / s$ (decreasing)
$∴$ $e = - 5 \times (- 2) = + 10 V$

Q. The current passing through an inductor coil of 5H is decreasing at the rate of 2A/s, the emf developed across the coil is

+10.0V

−10.0V

+2.5V

−2.5V

If on changing current through the coil, the emf induced in the coil ise, then by Faradays 2nd law, we have e=−LΔtΔi​ where, ΔtΔi​ is rate of change of current. Given, L=5H,ΔtΔi​=−2A/s (decreasing) ∴ e=−5×(−2)=+10V

$+ 10.0 V$

$- 10.0 V$

$+ 2.5 V$

$- 2.5 V$

If on changing current through the coil, the emf induced in the coil ise, then by Faradays 2nd law, we have
$e = - L \frac{Δ i}{Δ t}$
where, $\frac{Δ i}{Δ t}$ is rate of change of current.
Given, $L = 5 H, \frac{Δ i}{Δ t} = - 2 A / s$ (decreasing)
$∴$ $e = - 5 \times (- 2) = + 10 V$