Name: Magnetic Flux
Uploaded: 2019-07-19
Duration: 6 min 44 s
Description: Magnetic flux is the total number of magnetic lines of force that are passing through a given surface. To learn more about this intriguing concept, watch the...

Question

The coil in Figure, is rotating in a uniform magnetic field. Predict the direction of the current caused by induced e.m.f. in sections $A B$ and $C D$ . State which terminal, $X$ or $Y$ , will become positive.

Question Image

A coil rotating in a uniform magnetic field.

Accepted Answer

When the coil is in the position shown in the diagram, side $CD$ is moving down and side $C D$ is moving up. We can use Fleming’s right-hand rule to decide that end $Y$ will (at that instant) be the positive terminal of the generator. Remember, when using the rule, that conventional current flows away from positive towards negative outside the source of electrical energy, the generator in this case.When the coil has rotated through half a turn, and $X$ will be positive. Therefore, a coil rotating in a uniform magnetic field will have an alternating $e . m . f$ induced in it, of frequency equal to the frequency of rotation of the coil.

The coil is rotating in a uniform magnetic field using Fleming's right-hand (generator) rule Current flows from $A$ to $B$ and from $C$ to $D$ .

$Y$ Is positive so that current flows from $Y$ to $X$ In the external circuit to make it flow from $A$ to $B$ Inside the coil.

David Sang and Graham Jones Solutions for Chapter: Electromagnetic Induction, Exercise 3: Questions

David Sang Physics Solutions for Exercise - David Sang and Graham Jones Solutions for Chapter: Electromagnetic Induction, Exercise 3: Questions

Questions from David Sang and Graham Jones Solutions for Chapter: Electromagnetic Induction, Exercise 3: Questions with Hints & Solutions

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