Homework Help for Physics

70,524 results

Physics is the study of matter, motion, energy and force. It is a fundamental science that seeks to understand and explain the universe around us and beyond.

For unlimited access to Homework Help, a Homework+ subscription is required.

OC user
OC user
in Physics·
8 May 2019
A metal bar of length L is attached to two vertical metalrailsas sketched in the figure below. The connections arefrictionless,but allow current to flow between the rails and thebar. There is aconstant horizontal magnetic field directedperpendicular to thearea enclosed by the bar and rails.

(a) What closed path should we use for applying Faraday'slawto find the current induced in the bar? 1 Any closed loopwillwork. The perimeter surrounding the area enclosed by the barandthe rails should be the path chosen to use with Farday'slaw.
(b) Suppose the bar is at a height z above the bottom. Findthemagnitude and direction of the magnetic flux ΦB. (Use thefollowingvariables as necessary: B, L, and z.) magnitude ΦB =2 direction 3---Select--- out of the page into the page
(c) If the bar is moving downward at a speed v, is the fluxinpart (b) increasing or decreasing with time? 4increasingdecreasing
(d) What is the induced emf across the bar? (Use thefollowingvariables as necessary: B, L, and v.) || = 5 (e) Use youranswer topart
(d) to get the current I in the circuit. Be sure to givethedirection of I. (Use the following variables as necessary: B, L,R,and v.) magnitude I = 6 direction 7 ---Select---clockwisecounterclockwise
(f) Now find the magnetic force on the bar. Notice thatthemagnitude of this force increases as v increases. (Usethefollowing variables as necessary: B, L, R, and v.) F = 8
(g) What is the direction of the force on the bar? 9upwardsdownwards
(h) If the bar has a mass m, there will also be agravitationalforce on the bar. Eventually, the bar will reach aspeed v at whichthe gravitational and magnetic forces cancel sothat the total forceon the bar is zero. Find v. (Use the followingvariables asnecessary: B, g, L, m, and R.) v = 10
Please show work, I know this is a long question willratelife-saver !

Start filling in the gaps now
Log in