# Magnetic flux easy?

## Homework Statement

What is the magnetic flux through the loop shown in the figure below?

## Homework Equations

magnetic flux=ABcosANGLE

## The Attempt at a Solution

What I did is took 2*4e2 (because the area is 400cm converted to 4m) which equals 32
then 1*4e2 which is 16...Since one is going in and one is going out I thought you would minus 16 from 32 to give 16? Not correct? Any help?

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Welcome to the Forum
The area 20cm x 20 cm = 400cm2 That's correct...
But 400cm2 is not 4m (or 4m2)
It's 0.2m x 0.2m = 0.04m2

Flux is flux density in tesla times area in m2

No...because if i do that i get .0032 & .0016 which subtracted from one another equals .0016...still not right. I know the answer has to be so easy I'm missing it!?

collinsmark
Homework Helper
Gold Member
What I did is took 2*4e2 (because the area is 400cm converted to 4m) which equals 32
then 1*4e2 which is 16...Since one is going in and one is going out I thought you would minus 16 from 32 to give 16? Not correct? Any help?

Uhh, :uhh:

I don't seem to understand where you are getting values like 32 or 16.

Perhaps it would be easiest to do as Stonebridge implied, converting everything to meters first (instead of cm). The find the area, A, which equals length times width. Once you have the respective areas, incorporate the respective magnetic fields into things to find the flux.