- #1

- 149

- 4

## Homework Statement

A magnetic flux of 400 micro-webers passing through a coil of 1200 turns is reversed in 0.1 sec. Calculate the average value of the e.m.f. induced in the coil. (Hint use Faraday's Law)

## Homework Equations

## The Attempt at a Solution

So I know that

phi = F/R Wb

phi is flux

F is magnetomotive force MMF

R is reluctance

I also know that

F = N I

F is the MMF

N is the number of turns in the coil

I is the current in each turn

I now that faradays law is

E = - N * d[phi_B]/dt

Where E is the electromotive force (EMF)

N is the number of turns in each coil

phi_B is the magnetic flux through a single loop

Given:

phi_B = 400 micro Wb

N = 1200 turns

t = 0.1 s

solve for E

I don't see how to solve this problem. I know phi_B but not the derivative of it as a function of time. I also don't know the current. Any help would be greatly appreciated.