Warm Up What is the SI unit for charge? Calculate the electric force between two electrons that are 1.0 mm apart.

Electric Field Lines

Electric Field A measure of the electric force a positive test charge would feel at any location Test Charge – a unit charge used to measure the field

The farther apart the field lines, the weaker the force

Electric Field E = Fe / q Units: N/C E represents the strength of the electric field Ex: A positive charge of 1x10-5 C experiences a force of 0.2 N when located at a certain point in an electric field. What is the electric field strength at that point?

Drawing electric field lines

Which direction is the field pointing? On your own: Draw a single negative charge and draw the electric field around it Which direction is the field pointing?

Another try: Hint: which one is the field going away from? Copy this view of one positive charge and one negative charge, and draw the electric field you think they’d create… Hint: which one is the field going away from? And toward which one?

Electric dipole field

Parallel plates that are oppositely charged The electric field is the same at all points between parallel plates

What two things does an electric field tell us? Magnitude Direction