- #1

osugirl10

- 1

- 0

## Homework Statement

A piece of copper wire is formed into a single circular loop of radius 10 cm. A magnetic field is oriented parallel to the normal to the loop, and it increases from 0 to 0.70 T in a time of 0.45 s. The wire has a resistance per unit length of 3.3 10-2 /m. What is the average electrical energy dissipated in the resistance of the wire.

## Homework Equations

Emf = -NAB/t

P = V(^2)/R

E = Pt

## The Attempt at a Solution

I used The first equation to find emf... -.0489V

with that I plugged it into the second equation (for R I took my resistance per unit length times the circumference of my circle - pi*d)

so for my power I got .0489^2/.0207 = .1155

Then I thought I would just plug that number into the third equation

E = .1155w(.45s)

which would give me .052 J

but this isn't the right answer.

Where did I go wrong?