Gravitational forces depend on the property called mass. What comparable property underlies electric forces?
100
Contact and Friction
Which two methods of charging objects involve touching?
100
Both exert forces
How are a gravitational field and an electrical field similar?
100
It has a magnitude and direction
Why is an electric field considered a vector quantity?
100
120
How many joules per coulomb are givin to charges that flow in a 120-volt circuit?
200
Negligible potential difference across the body
Why is it that a bird can perch without harm on a high-voltage wire?
200
Volt
What is the SI unit for electrical potential?
200
The charges on the outside are mutually repelled and the electrical fields inside cancel to zero.
Why are occupants safe inside a car struck by lighting?
200
Ratio can be high when charge is small
How can electrical potential be high when electrical potential energy is relatively low?
300
Capacitor
A diode converts AC to pulsed DC. What electric device smoothed the pulsed DC to a smoother DC?
300
Negative on one side, positive on the other
What does it mean to say an object is electrically polarized?
300
A molecule in which the distribution of charge is uneven.
What is an electrical dipole?
300
The same; Coulomb's law can't distinguish between positive and negative charges
If electrons were positive and protons were negative, would Coulomb's be written the same or differently?
300
Form the conductors themselves
From where do the electrons originate that flow in a typical electric circuit?
400
60W = I x 120V; I = .5A
How many amperes flow through a 60-watt bulb when 120 volts are impressed across it?
400
I = q/t =(10 C)/(5 s) =2 A
Calculate the current where 10 coulombs of charge pass a point in 5 seconds.
400
I = V/R = (6 V)/(1200 ohms) = .005 A
How much current moves through your fingers (resistance: 1200 ohms) if you touch them to the terminals of a 6-volt battery?
400
Static charge is built up by rubbing.
Why will dust be attracted to a CD wiped with a dry cloth?
400
It sticks better to the non-conducting glass.
Plastic wrap become electrically charged when pulled from its container. Does the charged wrap stick better to glass bowls or metal bowls?
500
Charge is transferred. No net charge isn't ever created or destroyed.
If a glass rod isn't rubbed with a pastiche dry cleaner's bag acquires a certain charge, why does the plastic bag have exactly the same amount of opposite charge?
500
The electrons are attracted to the same numbers of protons in the penny
The five thousand billion billion freely moving electrons in a penny repel one another. Why don't they fly out of the penny?
500
The forces will be equal in magnitude
How will the forces between two charged particles compare when one particle has ten times as much charge as the other?
500
Yes, both are amounts of energy per some quantity
Does an object with twice the electric potential of another have twice the electrical potential energy? Explain
500
Strands of hair are charged with the same sign of charge and are mutually repelled
Why does your hair stand out when you are charged by a device such as a Van de Graaff Generator?