1. Force on an Electric Charge Moving in a Magnetic Field

2. F=qvB sin q

3. Right-Hand Rule Again

4. Important: right-hand rule defines direction of a force acting on a positive charge. For negatively charged particles the force is in exactly the opposite direction.
Don’t forget this when you are solving problems about electrons!!!

5. Electron’s Path in a Uniform Magnetic Field
An electron travels at velocity v in a plane perpendicular to a magnetic field. Describe its path.

6. Conceptual Example: A Spiral Path
What is the path of a charged particle if its velocity is not perpendicular to the magnetic field?

9. Magnetic Field Due to a Straight Wire

11. Force between Two Parallel Wires

12. Each current produces magnetic field that is “felt” by the other wire so that each must exert a force on the other.

13. Parallel current in the same directions attract each other, antiparallel currents repel.