A metal rod of miss m 100 g and length I 10 m rests on mo

A metal rod of miss m = 100 g and length I = 1.0 m rests on mo Cued, frictionless, conducting rails, as seen from above in tie diagram. Snitch S is closed at time t=0, allowing the batten K, = 50 V to generate current through the top rail, down through the rod, and then through the other rail back to the batten\'. The wires have a combined resistance R = 2 ohm and the are immersed in a uniform magnetic field of strength B = 0.02 T pointing downward (as shown) What is the current in the circuit at time t = 2.0 s? What is the force on the rod for time t > 0? What is the velocity of the rod at time t = 2.0 s?

Solution

a)

Current in the circuit is

I=V/R =50/2

I=25 A

b)

Force on rod

F=BIL =0.02*25*1

F=0.5 N

c)

Induced emf

E=BLv

=>v=E/BL =50/(0.02*1)

v=2500 m/s