Electro Magnetic Induction And Alternating Currents Question 508
In a coil of resistance 100 Ω, a current is induced by changing the magnetic flux through it. The magnitude of change in flux through the coil is
Options:
A) 250 Wb
B) 275 Wb
C) 200 Wb
D) 225 Wb
Show Answer
Answer:
Correct Answer: A
Solution:
- According to Faraday’s law of electromagnetic induction,
$ \varepsilon =-\frac{d\phi }{dt} $ Also, $ \varepsilon =iR $ $ \therefore V=Ri=\frac{d\phi }{dt}\Rightarrow \int{d\phi =R\int{i,dt}} $
Magnitude of change in flux $ (d\phi )=B\times area $ under magnetic field vs time graph or
$ d\phi =100\times \frac{1}{2}\times \frac{1}{2}\times 10=250\,Wb $
BETA
