This preview shows page 1. Sign up to view the full content.
Unformatted text preview: Problem 30.24 For the wire arrangement in figure 34, a = 12 cm and b = 16 cm . The current in the long straight wire is given by i = 4 . 5 t 2 10 t , where i is in Amperes and t is in seconds. (a) Find the emf in the square loop at t = 3 s . (b) What is the direction of the induced current in the loop? Figure 34: Figure for problem 30.24 The long straight wire is carrying a current and is therefore going to produce a magnetic field. B = μ i 2 πr ˆ φ where r is the distance from the wire. In order to calculate the emf in the square wire, we need to calculate the magnetic flux through the square as a function of time. Φ B = Z ~ B ( t ) · d ~ A The magnetic field is not constant over the area so we can not use our usual trick of pulling B out of the integral. We will actually have to integrate. We can simplify our lives a little by noting that the magnetic field points out of the page in the upper portion of the square and into the page in the lower portion of the square. Some of the flux through the lower portion will be canceled by thethe lower portion of the square....
View
Full
Document
This note was uploaded on 12/05/2011 for the course PHY 2049 taught by Professor Any during the Spring '08 term at University of Florida.
 Spring '08
 Any
 Physics, Current

Click to edit the document details