WOLFRAM|DEMONSTRATIONS PROJECT

Magnetic Force on a Sliding Bar

​
t
0.8
v
0
0.6
R
50
B
0.7
A conducting bar (green) moves over two frictionless parallel rails (yellow) with a resistance
R
. It creates a current due to the presence of a uniform magnetic field
B
that is directed into the figure (marked with ×'s). The bar has mass
m
, length
l
, and initial velocity
v
0
(blue) toward the right. After release at
t=0
, position and velocity as a function of time are shown. Note that the induced current is counterclockwise and the magnetic force
F
B
(orange) points in the direction opposite to the motion.