CHAPTER 18 - PHYSICS - ELECTRIC CHARGE
true
When a charge is established on an object, the change exists because the electrons have moved to or from the object. true false
false
It is impossible to detect types of charges with an electroscope. true false
false
J. J. Thomson found that electric charge is continuous, i.e., that any amount of charge was possible. true false
false
J. J. Thomson found the magnitude of an electron's charge. true false
false
J.J. Thomson found that electric charge is continuous, i.e., that any amount of charge was possible. true false
true
Like charges repel each other. true false
resinous electricks
Materials that acted like amber resinous electricks vitreous electricks
vitreous electricks
Materials that acted like glass resinous electricks vitreous electricks
false
Materials that hold their electrons firmly are called conductors. true false
true
Materials that hold their electrons loosely are called conductors. true false
false
Metals are generally poor conductors since they do not allow freedom of movement of their electrons. true false
true
Millikan discovered the magnitude of the fundamental charge. true false
true
Millikan found the magnitude of an electron's charge. true false
true
The electroscope is a device for detecting electrostatic charges. true false
false
The electroscope is good for measuring electric force. true false
true
The electroscope works best as a detector of charge. true false
true
The force of repulsion between two like charges is due to electrostatic force. true false
false
The force of repulsion between two like charges is due to static electricity. true false
false
The law of charges states that like charges attract and unlike charges repel one another. true false
true
The law of charges states that like charges repel and unlike charges attract each other. true false
true
The magnitude of the fundamental charge is the same for positive and negative charges. true false
Robert Millikan.
The scientist who discovered the charge of an electron was J. J. Thomson. Robert Millikan. Benjamin Franklin. William Gilbert.
J. J. Thomson
The scientist who discovered the electron was J. J. Thomson. Robert Millikan. Benjamin Franklin. William Gilbert.
true
The two ways by which a body may be charged are by contact and by induction. true false
true
Electrons had not yet been discovered in Franklin's time. true false
false
According to Coulomb's law, doubling the distance between two charged bodies will halve the force between them. true false
true
All electrical charges on atoms, molecules, and ions are multiples of the fundamental charge. true false
false
An electrick is any substance that can easily conduct electricity. true false
true
An electroscope's main purpose is to detect charges true false
true
An object is charged because electrons have traveled either to or from the object. true fe
false
An object is charged because protons have traveled either to or from the object. true false
true
Charles Du Fay's findings that there are two kinds of charge agree with our current knowledge. true false
an electrical fluid.
Benjamin Franklin and Charles DuFay assumed electricity to be a flow of negative charge. an electrical fluid. a solid or liquid. discontinuous. tiny particles that surround the atom.
false
Benjamin Franklin believed in the existence of electrons as the determiners of charge. true false
true
Benjamin Franklin called resinous electrification negative. true false
false
Benjamin Franklin called resinous electrification positive. true false
insulators
Both vitreous and resinous electricks are types of conductors. semi-conductors. insulators. semi-insulators.
torsion balance
Coulomb experimented with electrostatic forces using a(n) _____. oil-drop apparatus electroscope charged rod and dust particles torsion balance
Newton's law of universal gravitation
Coulomb's law is similar to which of the following laws? the first law of thermodynamics Newton's law of universal gravitation Newton's third law the law of the conservation of angular momentum
true
Coulomb's law states that the force between two charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them. true false
inversely proportional to the square of the distance between the bodies.
Coulomb's law states that the force of attraction between two charged bodies is directly proportional to the distances between the bodies. directly proportional to the square of the distances between the bodies. inversely proportional to the square of the distance between the bodies. inversely proportional to the product of the charges of the two bodies.
true
Doubling the distance between two charged objects will cut the force between them to one-fourth. true false
true
Electric charge is not continuous. true false
true
Electricity is the flow of electrons. true false
true
Electroscopes can determine the presence and sign of a charge. true false
true
Electrostatic force depends on the magnitudes of the distance and the charges. true false
true
Franklin and Du Fay both thought that the cause of electrification had something to do with fluids. true false
true
Franklin said that resinous electricks had a deficiency of negative fluid. true false
false
Franklin said that resinous electricks had a deficiency of positive fluid. true false
true
Franklin's idea about one fluid is close to the modern theory of electron flow for solids. true false
They were insulators.
Gilbert's electricks had what type of electrical properties? They were conductors. They were insulators. They were semiconductors. They had no special electrical properties.
false
Glass is a good conductor of electricity. true false
true
Glass is a good insulator of electricity. true false
true
Glass, amber, rubber, and Lucite are electricks true false
two
How many electroscopes does it take to demonstrate conduction? one two three four
two
How many electroscopes does it take to test conduction? one two three four
2
How many types of electricks are there? 1 2 3 4
false
If 2 objects repel each other, you know that they are both negative charges. true false
false
If the distance between two charged particles doubles, the force exerted between them will be halved. true false
false
If two charges exert an electrostatic force on each other and one charge is twice the other, then the larger charge will exert twice the force of the smaller charge and the smaller charge will exert half the force of the larger. true false
true
In early times, scientists thought that charged objects contained one of two types of fluids. true false
true
Induction of an electrostatic charge requires only the presence of a charged object not actual contact, to establish a charge in another object. true false
true
No charges have been found that are fractions of the charge of an electron. true false
true
Nonmetals are generally poor conductors since they do not allow freedom of movement of their electrons true false
true
On humid days, charged objects lose their charges more quickly because the presence of water vapor makes the air more conducive. true false
true
One esu of charge on each of two bodies 1 cm apart results in a force of 1 dyne.
true
Solids with many free (mobile) electrons are called conductors. Insulators contain few free electrons (their electrons are tightly held). true false
false
The SI unit of charge is the esu. true false
true
The charge of an electron, of which all charges are multiples, is called the fundamental charge. true false
established the fact that every electron carries a charge of the same magnitude.
Robert Millikan's oil drop experiment established the fact that every electron carries a charge of the same magnitude. did not actually measure the charge of an individual electron. always resulted in drops which were positively charged. yielded results showing that the charge was not always in discrete values.
a negatively charged rod is brought near the electrode. a positively charged rod is brought near the electrode. a negatively charged rod touches the electrode. a positively charged rod touches the electrode. a second negatively charged rod is brought near the electrode. a second positively charged rod is brought near the electrode.
Select all that apply. The leaves of an electroscope move from their original positions and separate if a negatively charged rod is brought near the electrode. a positively charged rod is brought near the electrode a negatively charged rod touches the electrode. a positively charged rod touches the electrode. a second negatively charged rod is brought near the electrode. a second positively charged rod is brought near the electrode. a second negatively charged rod touches the electrode (after a negatively charged rod had previously touched the electrode and been removed). a second positively charged rod touches the electrode (after a positively charged rod had previously touched the electrode and been removed).
Metals are conductors. They contain many free electrons. Electrons are loosely held.
Select all that apply. Which of the following is true of conductors? Metals are conductors. Glass is a conductor. Rubber is a conductor. They contain many free electrons. They contain few free electrons. Electrons are tightly held. Electrons are loosely held.
true
Semiconductors are materials that hold their electrons in a way that allows a flow of electricity only under certain conditions. true false
false
Solids that have many free electrons are called insulators. true false
true
Thomson disproved the continuous charge concept when he showed that all matter contained discrete units of charge. true false
true
Thomson showed that all matter contains separate and discrete charges called electrons. true false
false
Uncharged electroscope can be used to indicate the presence, sign, and magnitude of electrostatic charge on an object. true false
contact induction
What are the 2 ways to charge an object?
The leaves remain separated for an extended period of time.
What happens when you touch an electrified piece of amber to a neutral electroscope? The leaves separate momentarily, then fall back to their original position. The leaves remain separated for an extended period of time. The leaves do not respond to the electrified piece of amber. The leaves which were already separated separate even farther.
coulomb
What is the SI unit for charge? dyne electrostatic unit coulomb newton
an insulator
What must the stopper of an electroscope be made of? an insulator a conductor a semiconductor it does not matter
oil
What substance was used in the measurement of the fundamental charge? water oil acetone perfume
oil
What substance was used to measure the fundamental charge? water oil acetone perfume
true
When charge is added to an object by way of an electrical ground, it is most efficiently charged using the method of induction. true false
separate
When you bring a charged rod near the electrode of the electroscope, the leaves attract each other. separate. separate and then quickly move back together. do not move.
the earth
Which makes the best electrical ground for a large charge? a person the earth a tire an electroscope
iron
Which of the following is a conductor? glass ceramic plastic iron
There is no electrical charge that has been found to be a fraction of the charge of an electron.
Which of the following is true? Protons are a fraction of the charge of an electron. Neutrons are a fraction of the charge of an electron. All electrical charges are a fraction of the charge of an electron. There is no electrical charge that has been found to be a fraction of the charge of an electron.
an electrical ground
Which of the following is unaffected when electrons are added? an oil drop an electrostatic torsion balance an electroscope an electrical ground
porcelain
Which of the following substances is classified as an electrical insulator? porcelain tin copper mercury
William Gilbert
Who was/were among the first to experiment extensively on electrification? the Greeks Charles Du Fay William Gilbert Benjamin Franklin
Robert Millikan
Whose work disproved the idea that charged objects contained electric fluids by showing that charged objects possessed particles with a certain charge? William Gilbert Charles Du Fay J. J. Thomson Robert Millikan
because it eliminates static charge on the can
Why must you place a gas can on the ground before you add gasoline to it? because it's more stable because it's easier to fuel because it eliminates static charge on the can because you can more easily view the level in the can
conductors
__ contain many free electrons conductors insulators
insulators
___ contain few free electrons conductors insulators
resinous electricks
___ contained resinous fluids resinous electricks vitreous electricks