Question

What is the current in a wire loop of resistance 16 Ω through which the magnetic flux changes from zero to 84 Wb in 3 s?

Answer 1

Resistance of circuit (R)=16Ω

$Time (t)= 3\times 10^{-3} \;sec$

As we know that, emf is given as-

$e=\frac{dϕ}{dt}=\frac{84-0}{3\times10^{-3}}=28\times10^3\;V$

Therefore,

Current passing through the circuit is-

$I=\frac{e}{R}=\frac{28\times10^3}{16}=1750\;A$

$q=I\times t=1750\times 3\times 10^{-3}=5.250 \;C$

Hence the charge passed through the circuit during the given time is 5.25 C.