Physics 2 Mid-Term Quiz 1

A precious stone in 600B.C. that attracted pieces of dry leaves and feathers

Amber

Amber

Means elektron

Electricus

Of amber

William Gilbert’s Book

De Magnete

Planetary Structure

Created by Neils Bohr in 1913

Three Subatomic Particles of an Atom

Proton, Neutron, Electron

Mass of Protons and Neutrons

1.6 × 10^-27 kg

Mass of Electrons

9.1 × 10^-31 kg

Joseph John Thomson

Discovered the Electron

Ernest Rutherford

Discovered the Proton

James Chadwick

Discovered the Neutron

Positively Charged Atoms

When atom loses electrons

Negatively Charged Atoms

When atom gains electrons

Benjamin Franklin

Discovered that charges can either be positive or negative

When an object has too much/deficiency of electric fire

Positively Charged/Negatively Charged

Electric Charge

Basic property of matter carried by some elementary particles (such as electron)

Two Types of Electric Charge

Positive and Negative

Proton

+e = 1.602 × 10 ^-19 Coulomb

Electron

-e = 1.602 × 10 ^19 Coulomb

Charles Augustin de Coulomb

Made the SI unit Coulomb (C)

1 Coulomb

6.28 × 10^18 electrons

Fundamental Law of Charges

Opposite charges attract, like charges repel

Law of Conservation of Charges

Charges can neither be created nor destroyed. Charges can only be transferred

Conductors

• Materials that permit electrons to freely flow from

• Electrons are not tightly bounded

Insulators

• Materials that permit electrons to freely flow

• Electrons are tightly bounded, meaning they want electrons

Charging by Friction

• Two object should be physically contact

• Before: Both objects are neutral in charge

• After: Both objects are oppositely charged

Charging by Induction

• No physical contact

• Before: One object is charged (+ or -)

• After: Other object acquires opposite charge

Charging by Conduction

• Physical Contact

• Before: One object is charged (+ or -)

• After: Other object acquires same charge