A bar magnet with its north pole pointing toward a coil of wire with a cross sectional area of .03m^2 and 7 turns is thrust into a coil. If the rate of change in the strength of the magnetic field caused by the motion of the bar magnet is .06T/s, what is the magnitude of the induced emf in the coil of wire?

Question

anonymous · Answer

@AravindG Help? :D

aravindg · Answer

Okay do you know that induced emf is given by 

$$V=\dfrac{-Nd \phi}{dt}$$

anonymous · Answer

Do you have a simpler solution that does not involve derivatives?

aravindg · Answer

You should have derivatives or delta as question has  rate of change in the strength of the magnetic field. The solving part doesn't actually need it though.

anonymous · Answer

Delta is good.

aravindg · Answer

Now $$\phi=B.A$$

Replacing

$$V=-N \dfrac{\delta BA}{\delta T}=-NA \dfrac{\delta \phi}{\delta t}$$

aravindg · Answer

All the 3 terms are given! Calculate induced emf :)

anonymous · Answer

Oh... Faraday's Law. Well I feel stupid.

aravindg · Answer

You should not! These ideas come with practice! Do more problems, feel more comfortable!