Question

If the current in the toroidal solenoid increases uniformly from zero to $6.0A$ in $3.0\mu s$. Self inductance of the toroidal solenoid is $40\mu H$. The magnitude of self induced emf is :

• A. $80V$
• B. $160V$
• C. $24V$
• D. $48V$

Answer 1

The correct option is A $80V$

Current in toroidal solenoid increases uniformly from $0$ to $6.0A$ in $3.0\mu s$.
Magnitude of self induced emf is given by
$|ϵ|=L\left|\frac{di}{dt}\right|$
[Symbols have usual meanings]
$=(40\times {10}^{-6})\left(\frac{6-0}{3.0\times {10}^{-6}}\right)=80V$