Mocks Mistakes

Question 1

Remember for faraday equation to multiply through

Answer 1

By whatever constsnt there is

Question 2

For any emf to be induced the motion must be in a way so that it CUTS flux lines lit intercept

Answer 2

IT CANT GO ALONG so when it said horizontal and right angles it meant THROUGH THE PAGE

Question 3

When can you use BLV

Answer 3

ALWAYS!

A higher height means greater v due ti terminal ideas and thus greater emf

Reason it’s wacky is because entering id cue current leaving induce current other way ti stop it from leaving, somewhere in between must have gone to zero

As greater veocloty, thr time will be less

Question 4

Okay so when emf graph is shown, what to bare in mind for the axis

Answer 4

Yes if negative gradient shown on Flux graph, then mark as positive for emf

The emf on axis is negative emf, due to the equation

Now we see first section has a slower gradient than second, so it must be low and second one “higher”l

Question 5

Remember change of cos theta not theta

Question 6

When magent enters a coil and comes to rest, why is there a current induced snd then no linger

Answer 6

Putting magent in increases the flux experienced by coils, and as you move it along the flux does continue to change, and so current is induced for this time

I assume by lens law the force felt in return stops it form moving

When it’s stationary, there is flux ( because there is a B and A) but it’s CONSTANT

Constsnt flux = zero emf

The flux chasing is because different stentgh if the density is being cut by different wires etc as it’s moved slong

Question 7

For the coil being given current and then another coil a bit away, how do you know a firce is induced and what direction?

Answer 7

Well we know force will be id iced because as current givingen ti first coil, MAGENTIC field given.

This briefly changes flux in the second coil until it becomes constsnt, so current will be induced in second

As current induced by lens law a force induced too, but to COUNTER THE THING THAG MADE IT A

Thing that made it was a MAGENTIC FIELD form thr wire

Now whatever side was north or south, if a MAGENTIC field was north , the one from other coil can’t be south, because it would acts t, and create ENERGY out of nothing

So instead it has to REPEL, and thus go right!

Question 8

Remmeber tho always do final minus INITAL, at theta = 0 there will be some flux