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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Physics => Topic started by: ScreaMy on June 06, 2017, 10:43:49 pm

Title: EMF Question
Post by: ScreaMy on June 06, 2017, 10:43:49 pm
Hi Everyone,
I need help with the following question:

A coil of 500 turns, each of area 10cm2, is wound around a square frame. The plane of the coil is initially parallel to a uniform magnetic field of 80mT. The coil is then rotated through an angle of 90 Degrees so that its plane becomes perpendicular to the field. The rotation is completed in 20ms.

What is the average emf induced in each turn during this time?
Title: Re: EMF Question
Post by: TooLazy on June 07, 2017, 05:40:58 pm
2 Volts.

Convert everything into standard UI.

then use the formula

e = -N x (Delta Flux/Delta time)

note the the neg sign on N can be ignored for calculations
Title: Re: EMF Question
Post by: Bri MT on June 07, 2017, 05:43:03 pm
Emf= N (number of coils) * (delta phi)/(delta t)
We also know that because the coil has gone from being parallel to perpendicular, (delta phi or change in flux)= (delta B or change in magnetic field) multipled by (A or the area of the coil)

Make sure that you use SI units (eg convert from milliseconds to seconds)

Sorry if this isn't very helpful; it's difficult to type physics on my phone.