
Electricity and Magnetism
Free Response Question #3 Solutions  AP Physics C 1998 Released Exam
(25:48)
This Free Response Question includes the following concepts: Magnetic Forces, Current, Motional Emf, Newton’s 2nd Law, Magnetic Flux, Electric Potential Difference, Current, Resistance, Electric Power, Terminal Velocity and using the integral to find the speed as a function of time when the acceleration is not constant.
AP® is a registered trademark of the College Board, which was not involved in the production of, and does not endorse, this product. Enjoy an EDpuzzle Lesson for this video. Link: AP Physics C 1998 Released Exam The problem is on pages 168  169 of this pdf. Their solution is on pages 214  215 of this pdf. Please enjoy my solutions as well. Content Times: 0:30 A general description of the problem 2:09 Part (a) The Right Hand Rule! 4:18 Part (a) Breaking the Force of Gravity in to its Components 6:46 Part (a) Summing the forces in the Parallel Direction 8:40 Part (b) Deriving Motional emf 11:36 Part (b) Solving for Current 12:07 Part (c) Solving for Electric Power 12:56 Part (d) Reviewing the limits of the speed of the bar 14:06 Part (d) Summing the forces in the Parallel Direction (It’s a little bit different this time) 15:43 Part (d) Substituting in for the Current 16:37 Part (d) Integration! 18:42 Part (d) Substituting in the Limits 21:07 Part (d) Reflecting on how Part (d) was graded 22:33 Part (d) Checking our solution using the limits 23:56 Part (e) Determining what happens to the Equivalent Resistance 25:00 Part (e) Determining what happens to the Terminal Speed 

