Homework Help: Induced current in 2 cases

1. Jul 25, 2012

Deathnote777

1. The problem statement, all variables and given/known data
http://img831.imageshack.us/img831/9721/img20120725160304.jpg [Broken]
http://img542.imageshack.us/img542/653/img20120725160312.jpg [Broken]
Fig 1 is an AC generator
Fig 2 shows 2 solenoids
(ASSUME the area of coils in both fig1 and 2 are the same = A, resistance of 3-turn coils = R)
Is there any difference in the magnitude of the average current induced in 0.1s ?
What will be the change in current if I raise the no. of turns of coils from 3turns to 6 turns in both the AC generator and the right-side solenoid ?

The current should be the same in both figures, but in fig2 the current is halved if i apply conservation of energy.
2. Relevant equations
(3AB/0.1)/R = induced current in both setups
(6AB/0.1)/2R = induced current in both setups after winding 3 more turns

However, the actual induced current in fig2 i calculated is wrong. I should consider the conservation of energy. But isn't Fig1 and 2 are the same ? Can't I use the same method to do it ?
3. The attempt at a solution
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

Last edited by a moderator: May 6, 2017