# A-Level Physics

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#1
Any help would be appreciated!
Question 6ii:
https://pmt.physicsandmathstutor.com...0Induction.pdf

Mark Scheme:
https://www.physicsandmathstutor.com/physics-revision/a-level-aqa/fields/
- Electromagnetic Induction MS

For 6ii) Why can't you use EMF = BANω x sinωt?
Last edited by 234UncleBob; 2 months ago
0
2 months ago
#2
(Original post by 234UncleBob)
Any help would be appreciated!
Question 6ii:
https://pmt.physicsandmathstutor.com...0Induction.pdf

Mark Scheme:
https://www.physicsandmathstutor.com/physics-revision/a-level-aqa/fields/
- Electromagnetic Induction MS

For 6ii) Why can't you use EMF = BANω x sinωt?
Because the question asks for the average EMF generated.
In this case it simply needs the total change in flux divided by the total time taken.
The equation you refer to calcutales the instantaneous value of emf at a specific time, t, during the rotation. This is not what the question asks for.
Last edited by Stonebridge; 2 months ago
0
2 months ago
#3
(Original post by 234UncleBob)
Any help would be appreciated!
Question 6ii:
https://pmt.physicsandmathstutor.com...0Induction.pdf

Mark Scheme:
https://www.physicsandmathstutor.com...el-aqa/fields/
- Electromagnetic Induction MS

For 6ii) Why can't you use EMF = BANω x sinωt?
Sorry. Forum blip causes double reply to post. Ignore this one.
Last edited by Stonebridge; 2 months ago
0
#4
(Original post by Stonebridge)
Because the question asks for the average EMF generated.
In this case it simply needs the total change in flux divided by the total time taken.
The equation you refer to calcutales the instantaneous value of emf at a specific time, t, during the rotation. This is not what the question asks for.
So if it didn't say AVG then I was good?
0
2 months ago
#5
(Original post by 234UncleBob)
So if it didn't say AVG then I was good?
The question wouldn't make sense without the word 'average'.

The emf induced in the coil as it rotates through 90 deg varies according to your equation.
It depends on the angle the coil is making to the field at that time and thus on 't'.
So the question would have had to specify a time or angle at which the emf was to be calculated.
You would also need the value of ω to be constant. (The rate at which it was rotated.)
So your equation would be used in the context of knowing the angular velocity,ω, of the coil, and the specific time, t, at which the emf is wanted.
Last edited by Stonebridge; 2 months ago
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