Suppose that the light bulb in Figure 224b is a 600W bulb wi

Suppose that the light bulb in Figure 22.4b is a 60.0-W bulb with a resistance of 216 . The magnetic field has a magnitude of 0.492 T, and the length of the rod is 1.41 m. The only resistance in the circuit is that due to the bulb. What is the shortest distance along the rails that the rod would have to slide for the bulb to remain lit for one-half second?

Number _______ Units: m

Solution

Here ,

P = 60 W

R = 216 Ohm

B = 0.492 T

L = 1.41 m

let the speed of the rod needed is v

Now, for the potential across the bulb

P = V^2/R

60 = V^2/216

V = 114 V

Now, for the speed

V = B * v * L

114 = 0.492 * v * 1.41

v = 164 m/s

distance to be slided = v * t

distance to be slided = 164 * 0.50

distance to be slided = 82.1 m

the distance to be slided is 82.1 m