A conducting axle with mass m=15.3 kg and length L=1.50 m long rolls at constant
ID: 1788143 • Letter: A
Question
A conducting axle with mass m=15.3 kg and length L=1.50 m long rolls at constant velocity along a pair of conducting rails that are inclined 30 from the horizontal. A resistive load R=100 connects the rails, which are immersed in a uniform 0.800 T magnetic field that points downward.
(a) Determine the magnitude of the magnetic force on the axle.
(b) Determine the speed of the rolling axle.
Hints: Draw a free-body diagram. Separate forces into components, parallel and perpendicular to the rail. Take the inclination angle into account when computing the induced emf.
Explanation / Answer
a)
B = magnetic field = 0.8 T
F = magnetic force
magnetic force balances the component of force of gravity parallel to incline
F = mg Sin30
F = (15.3) (9.8) Sin30
F = 75 N
b)
current is given as
i = F/(BL) = 75 /(0.8 x 1.50) = 62.5 A
E = induced emf = iR
induced emf is also given as
E = BLv
hence
BLv = iR
(0.8) (1.50) v = (62.5) (100)
v = 5208.33 m/s
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.