Static Electricity

Review:What is inside the atom?

The atom is made of 3 kinds of particles.

The electron

The proton

The neutron

The Atom

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Insulators and Conductors

Insulators don’t let electrons flow through them

Conductors let electrons flow through them

Electrons stay stuck on the surface and don’t move—That’s STATIC ELECTRICITY!

Charged Objects

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Neutral Object

Negatively Charged Object

Positively Charged Object

How Do They Become Charged?

Contact

Electrons get

passed from one

object to the other

when they touch

Induction

Electrons in the

object move away

or towards another

charged object is

placed close to it

Friction

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What happens when you rub a balloon on your head and put it against the wall?

http://phet.colorado.edu/sims/balloons/balloons_en.jnlp

Uses of Static Electricity

Spraying a Car Positive Car

Negative Spraygun

The paint spreads out as each negative drop repels

No paint is wasted as the positive car attracts the negative paint

Removing Smoke from Power Station Chimnies

Positive Plate

Negative Plate

Charge up the Smoke

No smoke leaves the chimney

Earthing Petrol Tankers

Petrol rubbing against the pipe can build up a static charge which could cause an explosionThe tanker is joined to the ground with a wire to stop a charge building up

Lightning

What causes lightning?

Lightning is actually just static electricity on a much larger scale.

The rubbing is caused by air moving around

In thunderclouds bottom is usually negative and top is positive.

References

A Dercho Investigating Science 9 -Pearson