1. A conducting rod (L = 2.0 m) is moved along two conducting rails within a magnetic field (B). The rails are hooked up to a light bulb. The resistances of the rails and the rod are negligible, but the light bulb has a resistance of 100 Ω. The rod is moved at a velocity (v) of 10 m/s in the direction indicated. It induces a current (I) in the circuit as indicated in the figure. The magnetic field has a magnitude of 2.0 T and the direction is indicated in the figure. What is the magnitude of the induced electromagnetic field (EMF; ε)?

2. A solenoid has 100 coils/m of wire carrying a current of 10 A. What is the magnetic field produced by the solenoid?

3. A positive charge travels in a circle within a uniform magnetic field (see figure). The directions of the arrows show the velocity vectors. What is the direction of the force exerted by the magnetic field upon the charge?

4. A magnetic field of 0.5 T passes through an area of 6.3 cm2 that is perpendicular to the field. What is the magnetic flux?

5. The primary coil on a transformer has 100 loops. The magnetic flux changes by 10 Wb/s. What is the magnitude of the EMF (ε)?

6. A magnetic field exerts a force on a 10-cm length of wire carrying 2 A of current. The magnitude of the force is 0.1 N. What is the strength of the magnetic field?

7. A magnetic field (B = 1.0 × 1010 T) exerts a force of 1.6 × 10−3 N on a charge moving at 1 × 106 m/s perpendicular to the field. What is the magnitude of the charge?

8. Two wires are placed side-by-side as shown in the figure. The wires have currents of the same magnitude, but they are in opposite directions (indicated by the arrows). How will these wires interact?

9. A torus has 100 wires/cm wrapped completely around it. The radius of the torus is 0.5 m. The current through the wire is 10 A. What is the strength of the magnetic field at a point that is 1.0 mm from the outside edge of the torus?

10. A magnetic field of 1.0 × 10−4 T is experienced at a point located 5 cm from the center of a current-carrying wire. What is the magnitude of the current in the wire?

11. This figure is a schematic drawing of a magnetohydrodynamic propulsion unit. The electrodes create a current of ionized seawater as shown by the arrows between them. The direction of seawater and the magnetic field have been indicated. What will be the direction of thrust created by the unit?

12. A proton moves at a speed of 5.0 × 106 m/s at an angle of 30° relative to a magnetic field. It experiences a force of 4.8 × 10−13 N. What is the strength of the magnetic field?