1. Forces on Current Carrying Wires

2. If a current carrying wire produces a magnetic field, we should expect that magnets exert a force on the wire Direction of the force is perpendicular to the direction of the current flow and perpendicular to the magnetic field

3. Right Hand Rule Fingers point in the direction of the magnetic field, thumb in the direction of the current, palm points in direction of the force on the wire

5. Magnitude of Force Right hand rule tells direction but not amount of force Force is directly proportional to the current (I), length of wire (l), strength of magnetic field (B) and also depends on angle between I and B

6. Equation F = I l B sin  When I and B are parallel, the sin of the angle is 0 so no force is acting Force is at its max when I and B are at 90° Unit of B is the tesla (T) –1 T = 1 N/ A m

7. Example A wire carrying a 30 A current has a length of 12 cm and is placed between the pole faces of a magnet at an angle of 60°. The magnetic field is.90 T. What force acts on the wire?

8. Example A rectangular loop hangs in a magnetic field pointing up. If a current of.245A flows counterclockwise through the loop, and a force of.0348N acts, what is the magnitude of the magnetic field? What direction does the force act?