The figure below shows two parallel conducting rails, oriented vertically, conne
ID: 2264427 • Letter: T
Question
The figure below shows two parallel conducting rails, oriented vertically, connected to each other at the top by a wire with a resistance R. A conducting metal rod is oriented horizontally and is in contact with the two vertical rails. The horizontal rod has a length
and mass 28.3 g. The rod is released from rest at location A and begins to fall through a region of uniform magnetic field indicated by the shaded area in the figure. When the rod reaches point B, there is an induced current of 2.25 A flowing to the left in the rod, and the rod is moving downward with an acceleration of magnitude 7.85 m/s2.
Explanation / Answer
force on the conducting rod = mg = ilB sin theta
so ilB = 2.25* 0.047 * B = 0.0283 * 9.8
B = 2.62 T
direction is upwards