7 2 Electric Force acts on objects even

7. 2 Electric Force acts on objects even when not touching Objects with like charges repel one another Neutral objects are attracted to charged objects The amount of electric force depends on the amount of charge and the distance separating the objects • Increasing the charge increases the electric force • Decreasing the distance between charged objects increases the electric force • An object can become charged by either conduction or induction • • 1

7. 2 Electric Force • Force is… a push or a pull • Types of forces… a contact force or an action-at-a-distance force What type of force is an Electric Force? 2

Electric Force is an action-at-a-distance force • Force can be applied to an object without touching it • It is a push or a pull between two charged objects 3

Electric Force Not touching! 4

The Laws of Static Charge 1. Opposites charges attract 2. Like charges repel + 3. Neutral objects are attracted to charged objects + - + 0 5

The Laws of Static Charge g Opposites charges attract 1. 2. Like charges repel 6

The Laws of Static Charge 3. Neutral objects are attracted to charged objects 7

Electric Force Increases when… • the amount of charge between objects increases • the distance between charged objects decreases Electric Force Decreases when… • the amount of charge is decreased • the distance between charged objects increases 8

Charging by CONDUCTION • Charging a NEUTRAL object by touching it with a CHARGED object 9

Charging by INDUCTION • No electrons are transferred between objects • Electrons are repositioned inside the object 10

The Attraction of NEUTRAL OBJECTS • The part of the NEUTRAL wood block closest to the balloon has a POSITIVE CHARGE because the electrons in the wood block are REPELLED due to INDUCTION 11