A piece of copper wire is formed into a single circular loop of radius 18 cm. A magnetic field is oriented parallel to the normal to the loop, and it increases from 0 to 0.54 T in a time of 0.57 s. The wire has a resistance per unit length of 4.9 x 10-2 /m. What is the average electrical energy dissipated in the resistance of the wire

Can anybody me with this? ? (picture included.)

I'm thinking it's 2 you are asked to explain the earth's magnetic field. which is the best reply? 1. the earth's magnetic south is similar to the north pole of a magnet. 2. the earth's core has a strong magnetic charge similar to the south pole of a magnet. 3. the earth's geomagnetic south is similar to the south pole of a magnet. 4. the earth's magnetic charge is not centered at either pole; it varies based on location.

Point charges q1 = 51 µc and q2 = −27 µc are placed 1.0 m apart, with q2 on the right. what is the force (in n) on a third charge q3 = 19 µc placed midway between q1 and q2? (assume the positive direction is to the right. indicate the direction with the sign of your answer.)