Static Electricity

Static Electricity lesson illustration

Name the 3 particles in the atom.
What is the charge of each particle?

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Static Electricity
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jenvan3

Unit III Electricity & Magnetism

Static Electricity Intro

Fill In the Blanks Notes

I. Static Electricity - electronic charges flowing in no particular direction. (trapped in a body)

A) Electricity of the Atom

Atoms are
ordinarily neutral

#p = #e-

n has no charge

p has +1 charge

e- has -1 charge

Charge electron

-1.6 x 10^-19 Coulombs
(Reference)

Static Electricity lesson illustration

Did you know ....

Benjamin Franklin
Showed Them The Physics

National Portrait Gallery, London: NPG 327
Author - Joseph Siffred Duplessis (died 1802)

coined the terms positive and negative for electrical charge
proved lightning was static electricity
invented lightning rod
built a static electricity generator

Ben Franklin
- Pioneering Physicist

Franklin
- World Famous American
(For Physics)

1. Atoms become charged by gaining or losing ...

Electrons

Static Electricity lesson illustration

3 Big Rules of Electrostatics

Opposites Attract

Likes Repel

Only Electrons Move

(Protons move, but don't leave nucleus)

Static Electricity lesson illustration

Charge plates can deflect an electron

Mg⁺²		F^-1
Mg atom Lost 2 electrons		F atom gained 1 electron

20 p , 18 e-
What's the charge?

+ 2

Why are protons never lost or gained?

Protons are held in the nucleus by the strongest forces in the universe

a) Ion: electrically charged particle:

Charge is unbalanced

negative charge

#e > #p

positive charge

#p > #e

2. Charged objects lose their charge when grounded. (become neutral)

[ Flash ]

"What is the

bottom prong of

a plug called?"

Static Electricity lesson illustration

"The bottom prong of
a plug called the ground.
It discharges any excess
charge that may develop
in an electrical device"

When grounded:

Negatively charged objects ...

... lose electrons

and become neutral.

Positively charged object ...

... gain electrons

and to become neutral.

A cork ball hangs straight with no force inside a positively charged metal can, while a charged cork ball outside the can is pushed away

NYSSLS Reading Passage · Electricity & Magnetism

The Electrician of Philadelphia: How Benjamin Franklin Gave Electricity Its Language

Open Reading Passage → Regents Practice Version →

Check Your Understanding

5 quick questions — pick an answer to see if you’re right.

1. An atom is ordinarily neutral. What does that mean?

2. Atoms become charged by gaining or losing which particle?

3. An ion has 20 protons and 18 electrons. What is its net charge?

4. An object gains 3 extra electrons. What is its net charge? (Electron charge = −1.6 × 10⁻¹⁹ C)

5. A positively charged object is grounded and becomes neutral. What happened?

NYSSLS Regents Practice · Electricity · Charge Transfer

Static Cling in the Dryer

When clothes tumble in a dryer, different fabrics rub together. Afterward, a wool sock sticks to a polyester shirt. Tests show that the shirt is negatively charged.

Which statement best explains why the sock and shirt stick together?

▶ Want a challenge? Open 6 more Regents-style questions (harder · mixed formats)

Challenge score: 0 / 6

Substitute values

C1. After drying, the polyester shirt has a charge of −4.8 × 10⁻⁸ C. Substitute numerical values into a mathematical representation that can be used to determine the number of excess electrons on the shirt. Then calculate the number of excess electrons.

n = ( × 10⁻⁸ C)( × 10⁻¹⁹ C) = × 10¹¹ electrons

Multiple choice

C2. A charged balloon sticks to a neutral wall. Why?

Support or Refute · Justify

C3. A student makes the following claim about the sock–shirt system.

Claim: The wool sock lost exactly the same number of electrons that the polyester shirt gained.

Place a check mark in either the Support or Refute box. Justify your response using the law of conservation of charge.

Support Refute

Select all that apply

C4. Place a check mark in three boxes to indicate the changes that would reduce static cling in a load of laundry.

Run the dryer longer so the clothes are extra dry Remove the clothes while they are still slightly damp Add more polyester shirts to the wool load Dry the wool items and polyester items in separate loads Raise the dryer temperature Hang the clothes to dry in humid air instead of using the dryer

Multiple choice

C5. Dryer sheets coat fabric with a substance that slightly conducts electricity. How does this reduce static cling?

Constructed response

C6. Attraction alone cannot prove that the sock is charged, because a charged object also attracts neutral objects. Describe a test, using a glass rod that has been rubbed with silk (positive), that would show the sock is positively charged. State the expected result and explain why it is conclusive.

The Electroscope →