Warm-up(Own Paper!!)

What is kinetic energy?– It is the energy due to motion or the energy of

moving objects.

What happens to kinetic energy when a ball is thrown up into the air. – Gravity converts the kinetic energy into

potential energy.

Warm- Up

Where is the force of gravity directed?– Down

What is the acceleration due to gravity?– 9.8 m/s2

What are the two types of charge?– Positive & Negative

8-1: Electric Charge

Analyze factors that affect the strength and direction of electric forces and fields.

Describe how electric forces and fields affect electric charges.

Describe how electric charges are transferred and explain why electric discharges occur.

Electric Charge

Electrical energy– Energy associated with electrical charges.

Electrical charges– A property that causes subatomic particles

such as protons and electrons to attract and repel each other.

Protons – positive

Electrons – negative

Charged objects

Objects become charged because there is an imbalance of protons and electrons.

Positive charge– More protons than electrons.

Negative charge– More electrons than protons.

Uncharged – Equal numbers of each.

Charging Objects

Friction– Rubbing two objects together.– Balloon on hair, shoes on carpet, etc.

Conduction– Charge is transferred by contact.

Induction– A transfer of charge with out physical contact.

Conservation of Charge– The overall charge in the isolated system

remains constant.

Conduction

Induction

Electric forces

Like charges repel.

Opposite charges attract.– The electric force between two objects is

directly proportional to the net charge on each object.

– The electric force is indirectly proportional to the square of the distance between each object.

Electric Fields

The space around the electric charge over which the charge exerts a force.

Electric field strength depends on:– The amount of charge that produces the field.– The distance from the charge.

2 Forms of Electricity

1. Static – a build up of charge on an object

2. Current – a steady flow of electrons through a conductor

Conductors and Insulators

Conductors:– Allow a free flow of

electrons– Ex. Metals

(the wire inside an electrical cord)

Insulators:– Slow or stop the

flow of electrons.– Ex. Rubber, Glass,

Plastic(the rubber coating on the outside of an electrical cord)

Conclusion

Write a short paragraph describing the interactions between charges.– Two types of charges– The forces between charges– Way charges are transferred to and from

surfaces.