Hello Everyone, I can't seem to understand why the graph of Induced emf vs angle of rotation is sinusoidal. (you will need the link).

http://www.citycollegiate.com/generator1.gif

My thinking goes like this, if the coil is vertical (like in the first picture, θ=0) it means it is perpendicular to the B-field, meaning that magnetic flux is at a maximum. Now in the graph when the angle of rotation is 0

The equations would also follow, because flux is given by BAcosθ and if θ=90

Then emf is given by (n x change in flux)/ change in time

which means if flux is 0 then emf is 0.

Thanks for the help.

http://www.citycollegiate.com/generator1.gif

My thinking goes like this, if the coil is vertical (like in the first picture, θ=0) it means it is perpendicular to the B-field, meaning that magnetic flux is at a maximum. Now in the graph when the angle of rotation is 0

^{o}, why is the emf shown on the graph 0? Shouldn't it be if flux is maximum then emf should also be maximum, then in the second position of the coil (90^{o}) shouldn't the emf be minimum as flux is paralell to the field meaning flux is 0.The equations would also follow, because flux is given by BAcosθ and if θ=90

^{o}then flux would also be 0.Then emf is given by (n x change in flux)/ change in time

which means if flux is 0 then emf is 0.

Thanks for the help.

Last edited: