Terms in this set (28)
charging by friction
When two dissimilar objects are rubbed together, one object loses electrons and the other object gains electrons, so one object gets a net positive charge and the other gets a net negative charge.
Charging by conduction involves contact with the source of the charge.
Charging by induction is charging indirectly. The source and the object never touch when charging by induction.
when does an object feel an electric force
The field lines are drawn from positive sources and toward negative sources, and show the direction a positive test charge would move if placed in the electric field.
Electric potential is the work required to move a test charge from one point to another. It is the potential energy per charge.
what is an electric potential
The potential is high.
charge when an object uses an induction but has a negative source
charge when an object uses conduction but has a positive source
coulombs law states that the electrostatic force is dependent on...
The force is dependent on the charge of the two objects and the square of the distance between them.
which force is stronger? gravitational or electromagnetic?
The electrostatic force is stronger. The gravitational force dominates because most objects are electrically neutral and since the earth's mass is so large, the gravitational effects become significant.
does friction involve grounding? does charging from conduction involve grounding? does charging from induction involve grounding
Friction charging does not involve grounding. Charging by conduction does not involve grounding. Charging by induction does not need grounding, but grounding can be used.
(using coulomb's law) if the distance between two charges is halved, what happens to the force?
The force is quadrupled.
what are the units of electric potential? electric field?
Volts (or Joules / Coulomb). N/C. Coulomb. Joules.
can a neutral object ever be repelled by a charged object? can it be attracted by a charged object?
A neutral object can never be repelled by an object. It can be attracted to a charged object.
do electric field lines cross? why?
Electric field lines never cross because they show the direction of the net force, and there cannot be more than one net force at a single location.
what causes the leaves of the electroscope to separate?
Like charges in the metal leaves cause them to repel each other.
what is the electric field inside a conductor?
The electric field is zero inside a conductor. All the charges are on the surface of the conductor.
assuming that the electrostatic force remains constant, what happens to the electric field when the charge is doubled?
how do you know what direction electrostatic forces are?
. The electrons move and cause your individual hairs to become negatively charged. The like charges repel each other and your hair is light enough so that the electrostatic forces overcome the gravitational forces.
how do you know a negatively charged object will react in an electric field?
Draw a diagram of the problem. Like charges attract and unlike charges repel.
what is a conductor?
A conductor is something that freely gives up or accepts electrons (charge is redistributed in a conductor).
what is an insulator?
An insulator is a material that doesn't allow electrons to move easily.
what is grounding?
Grounding is neutralizing an object by sharing its charge with the earth.
what is polarization?
They have negative energy
if a hanging object is attracted to a charged object, can you assume that the hanging object is also charged?
No. The hanging object could be charged or neutral.
why is a charge transferred by electrons and not protons?
Electrons are less massive than protons (2000 times smaller).
a positive charge and a negative charge are sitting next to each other. what is their potential energy?
When the charges are next to each other the potential energy is zero.
if the charges are separated what can you say about the potential difference?
After they are moved, the potential difference is positive.