ps09

# ps09 - MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of...

This preview shows pages 1–3. Sign up to view the full content.

Problem Set 09 p. 1 of 5 MASSACHUSETTS INSTITUTE OF TECHNOLOGY Department of Physics 8.02 Fall 2008 Label with your name, table number and group. Turn in at the homework box. Problem Set 9 Due: Thursday, November 6 th at 12:00 pm Warm Up Problem 1: Magnet Moving Through a Coil of Wire Suppose a bar magnet is pulled through a stationary conducting loop of wire at constant speed, as shown in the figure below. Assume that the south pole of the magnet enters the loop of wire first, and that the center of the magnet is at the center of the loop at time t = 0. (a) Sketch qualitatively the magnetic flux B Φ through the loop as a function of time. (b) Sketch qualitatively the current I in the loop as a function of time. Take the direction of positive current to be clockwise in the loop as viewed from the left. (c) What is the direction of the force on the permanent magnet due to the current in the coil of wire just before the magnet enters the loop? (d) What is the direction of the force on the magnet just after it has exited the loop? (e) Do your answers in (c) and (d) agree with Lenz's law? (f) Where does the energy come from that is dissipated in ohmic heating in the wire?

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document