You have a battery with known emf = K, a sensitive voltmeter, and a slab of high-resistance metal in which the mobile charges are electrons with mobility u; there are n electrons per cubic meter. The...

You have a battery with known emf = K, a sensitive voltmeter, and a slab of high-resistance metal in which the mobile

charges are electrons with mobility u; there are n electrons per cubic meter. The metal slab has length L, height h, and width

w. You also have plenty of very low-resistance wires you can use to connect the components in Figure 21.110 together.

There is a uniform magnetic field pointing up throughout the region where the slab is located; this magnetic field is

produced by a large magnet that is not shown. The goal is to figure out the magnitude B of this magnetic field, using the

available equipment.