Question

The magnetic flux of $50\mu Wb$ passing through a 200 turns coil is reversed in $2\times {10}^{-3}$ seconds. The average e.m.f induced in the coill in volts is

• A. 2.5
• B. 5
• C. 7.5
• D. 10

Answer 1

The correct option is B 5

Given that,

Magnetic flux, $\varphi =50$μ Wb

Number of turns, $n=200$

$dt=2\times {10}^{-3}$

Now,

Induced e m f

$e=-n\frac{d\varphi }{dt}$

$e=-200\times \frac{50\times {10}^{-6}}{2\times {10}^{-3}}$

$|e|=5$

Hence, the average e m f induced in the coil is 5 volt.