In the figure a long rectangular conducting loop of width L

In the figure, a long rectangular conducting loop, of width L = 18 cm, resistance R = 7.8 ?, and mass m = 0.087 kg, is hung in a horizontal, uniform magnetic field of magnitude 1.5 T that is directed into the page and that exists only above line aa. The loop is then dropped; during its fall, it accelerates until it reaches a certain terminal speed vt. Ignoring air drag, find the terminal speed.

Solution

V = m g R / B² L²

= (0.087 * 9.8 * 7.8) / (1.5² * 0.18²)

= 91.22 m/s