PY 131 Module 17 - Electrostatics

Coulomb’s Law/Force of electricity formula

F = (K)(q1q2/r²)

K: Coulomb’s constant

q: charges

r: radial distance

The electric field is analogous to which other kind of field

Gravitational field

Conservation of charge

Charges carried by protons and electrons which are always equal in number, and thus net total charge always Remains the Same

According to the conservation of charge principle the total number of electrons..

Always Remains the Same

What force holds electrons in orbit about the atomic nuclei

The electric force

How is electric force dissimilar to gravitational force

Electric force attracts as well as repels

The fundamental rule of electricity has to do with..

The attraction and repulsion between electric forces

Denominals tend to be good or bad conductors

Poor conductors

What is a transistor

It uses semiconductor properties to control the flow of electrons within a circuit to amplify electrical signals

What can result in the build of electric charge

Sliding physical contact or induction

How to lightning rods work

Electric charges quickly dissipate from sharp metal points

Rising atmospheric water vapor tends to pick up electrons from..

Ice crystals

Why can electrically neutral materials be attracted to either positive or negative charges

Because of the mobility of the atoms and molecules within that material

As an insulating material becomes polarized what flips

Molecules

What wins when it comes to charge polarization?

Closeness

An electric field is actually

A force field

An electric field is a vector or scalar quantity

Vector quantity

The magnitude of electric field inside a metal dome is

Zero

Electric potential is electric potential energy

Per unit of charge

When work is done on an electric

Energy increases

Even though vendograph films have very high voltages you can touch them with minimal harm because they have very little

Energy

It's a comb becomes positively charged as you comb your hair what happens to your hair

It becomes negatively charged

A two coulomb charge experience as a force of 60 newtons. The electric field at its location is

30 N/C

What happens to a pitbull hanging by a nylon string as a negatively charged Rod is brought close to it

The ball becomes polarized

What's around every proton in this universe

An electric field and a gravitational field

Why do we have lightning rods

To discharge the structure to which it is attached

What does an atom become when you strip away electrons

Positive ion

Two charges 1 M apart exert a force on each other of one newton. What would be the force if you were to push them to 0.25 m apart?

16 N

Two charges 1 M apart exert a force on each other of one newton. What would be the force if you were to pull them three meters apart?

0.11 m

Light from a pair of closely spaced stars does not produce an interference due to their

Incoherence

A rubber party balloon is charged to thousands of volts. But the spoon will have only a small amount of what?

Charge and energy

Two charges attract each other. If one charge is doubled along with the distance between them what is the resulting force?

2 F

What is a coulomb unit of charge equal to?

A specific large number of electrons

When is the electric force between two charges the strongest?

When charges are close together

What happens to the number of electrons in a capacitor as it is charged

The number remains unchanged

How do protons and electrons interact

They attract each other

Is lightning strikes a car what is the electric field inside the car

Zero

Particle X has double the charge of nearby particle Y. Compared to the force on particle x what is the force on particle y?

The same

The foil leaves of an electroscope are positively charged as they stand away from each other. What happens next as a negative charge is brought close to the head of the electroscope?

The foil leaves spread farther apart.

What is the force responsible for chemical reactions

The electrical force

What does it mean to say that a material is polarized electrically?

It's charges have been rearranged

It takes you 10 joules of work to push one coulomb of charge into an electric field. You let go and the charge accelerates back to the original position where it has a kinetic energy of what?

10 jewels

As described by The Vault electric potential is the ratio of what to what?

Electric energy to charge

What is the net charge on a capacitor

Zero

On one corner of a square is placed to charge which gives an electric field of F/q at the center of the square. What then is the field at the center when identical charges are placed at all the other corners?

Zero

Two oppositely charged particles in close proximity cause each other to move. As the particles move what happens to the force between them?

The force increases

Inside an uncharged aluminum Hollow ball the electric field is zero. As the ball becomes negative what happens to the field inside the ball?

The field remains zero

What happens to the charge of a comb as it grabs electrons from your hair

The comb becomes negatively charged

A balloon with a negative charge is held close to an aluminum can sitting on an insulated table. What happens to the overall charge of the can as you touch the opposite side?

The can becomes positively charged

Two charged particles in close proximity cause each other to move with increasing velocity. What does this tell you about the charged particles?

They have either the same or opposite signs

There's a gravitational attraction and an electric repulsion between two adjacent protons. Which is greater?

The electrical repulsion

To charge particles and close proximity cause each other to move. As the particles move the acceleration of each decreases. What does this tell you about the particles?

They have the same sign

What happens to the electrical force between two charges when the distance between them is halved?

The fourth quadruples

Within a given field which experience is greater acceleration and electron or a proton?

The electron

If it takes you 10 joules of work to pull one coulomb of charge away from an electric field what is the voltage of that charge in its new position?

10 volts

As two charged particles move toward each other the force on each particle increases. What does this tell you about the charged particles?

They have opposite signs.

What does it mean to say that the charge of an object is quantized?

The charge of the whole number multiple of the charge of one electron

What kind of charge does a balloon need to stick to a wooden ball

Either a negative or positive charge

What force holds atoms together in molecules

The electrical force

A building gets struck by lightning. It would be a worst case scenario if the building's frame was made of what material?

Wood

If two particles interact with each other but one has twice the charge of the other how do the forces on the particles compare?

They're the same

To charged particles held post to each other are released. As they move the force on each particle increases. Therefore the particles have?

Opposite signs