Calculating Microwave Oven Energy Transfer: What Information Do I Need?

[ninjadrummer8]

Homework Statement

I need to find the energy transferred per unit time from a microwave oven, and the only information I have is:

Wavelength = .122m
Peak Magnetic Field of microwaves = 1.3*10^-5 T

Homework Equations

c=f*lambda
I = (c*B^2)/(permeability of free space) = EB / (permeability of free space)

The Attempt at a Solution

My problem is I need either "c" or "f" in c=f(lambda) OR the electric field... I think? I'm not quite sure what to do.

 

[Redbelly98]

I = (c*B^2)/(permeability of free space)

You can find I from the given B. Two more things to think about:

1. Using the peak B given will result in the peak of I. What will be the average of I?

2. How does I relate to power?

 

[ninjadrummer8]

Ok, but I run into the same problems again. I have neither c nor E so I am stuck with 3 unknowns.

 

[Redbelly98]

But you do have c. Think about it ... what is c?

 

[ninjadrummer8]

OH! I'm an idiot. c is just the speed of light isn't it? so 2.99 x 10^8 m/s

 

[Redbelly98]

c is just the speed of light isn't it? so 2.99 x 10^8 m/s

Yes.