PHY 103 - Electrostatics

if 10 J of work is used in pushing 1 C of charge into an electric field, its electric potential relative to its starting position is: a) 10 V b) more then 10 V c) less than 10 V d) none of the above

a) 10 V

a common naturally-polarized bit of matter is: a) a water molecule b) a hydrogen atom c) an electron d) all of the above e) none of the above

a) a water molecule

an uncharged pith ball is suspended by a nylon fiber. When a negatively-charged rubber rod is brought near the pith ball, without touching, the ball: a) becomes polarized b) becomes charged by induction c) is unaffected d) is repelled by the rod e) none of the above

a) becomes polarized

the electrical force between charges is strongest when the charges are: a) close together b) far apart c) either of these d) need more information

a) close together

the force that binds atoms together to form molecules is: a) electrical b) centripetal c) nuclear d) gravitational e) none of the above

a) electrical

an electrically charged atom is an: a) ion b) isotope c) both of these d) neither of these

a) ion

to become a positive ion, an atom must: a) lose an electron b) gain an electron c) lose a proton d) gain a proton

a) lose an electron

a positively-charged rod is held near an aluminum can that rests on a dry wood table. If you momentarily touch the opposite side of the can with your finger, the can becomes: a) negatively charged b) positively charged c) partially discharged d) completely discharged e) none of the above

a) negatively charged

if you comb your hair and the comb becomes positively charged, then your hair becomes: a) negatively charged b) uncharged c) positively charged

a) negatively charged

the unit of electric charge, the coulomb, is the charge on a: a) specific large number of electrons b) specific number of neutrons c) single electron d) neutron e) quark

a) specific large number of electrons

the vast numbers of electrons in a coin don't fly off the surface because: a) they are attracted by an equal number of protons b) they are strongly bonded to their atoms c) mutual repulsion is incomplete d) all of the above e) none of the above

a) they are attracted by an equal number of protons

insulating materials are composed of atoms with: a) tightly bound outer electrons b) vastly more charge than conductors c) excess protons d) weak cohesive forces

a) tightly bound outer electrons

an electron and a proton: a) repel each other b) attract each other c) neither attract nor repel each other

b) attract each other

the primary purpose of a lightning rod is to: a) induce a charge opposite to that of charged clouds overhead b) discharge the structure to which it is attached c) cancel the electric field within the structure to which it is attached d) attract lightning and guide it to the ground

b) discharge the structure to which it is attached

in an electrically neutral atom the number of protons in the nucleus is equal to the number of: a) both electrons and neutrons b) electrons that surround the nucleus c) neutrons in the nucleus d) none of the above

b) electrons that surround the nucleus

to become a negative ion, an atom must: a) gain a proton b) gain an electron c) lose a proton d) lose an electron

b) gain an electron

conducting materials are composed of atoms with: a) vastly more charge than insulators b) loose outer electrons c) strong cohesive forces between them d) excess neutrons compared with protons

b) loose outer electrons

which of these does NOT have an electrical charge? a) proton b) neutron c) electron d) all of the above e) none of the above

b) neutron

when the distance between two charges is halved, the electrical force between them: a) halves b) quadruples c) doubles d) is reduced by 1/4 e) none of the above

b) quadruples

two charges that are separated by one meter exert 1-N forces on each other. if the magnitude of each charge is doubled, the force on each charge is: a) 2 N b) 8 N c) 4 N d) 1 N e) none of the above

c) 4 N

a fundamental rule of electricity is that: a) unlike kinds of charges attract b) like kinds of charges repel c) both of these d) neither of these

c) both of these

a semiconductor can be: a) an insulator b) a conductor c) both of these d) neither of these

c) both of these

normally a small party balloon charged to several thousand volts will have a relatively small amount of: a) charge b) energy c) both of these d) neither of these

c) both of these

the electrical force between electric charges depends only on their: a) magnitude b) separation distance c) both of these d) neither of these

c) both of these

it is said that electric charge is conserved, which means that electric charge: a) is a whole number multiple of the charge of one electron b) may occur in an infinite variety of quantities c) can be neither created nor destroyed d) will interact with neighboring electric charges e) is sometimes negative

c) can be neither created nor destroyed

a balloon will stick to a wooden wall if the balloon is charged: a) positively b) negatively c) either of these d) neither of these

c) either of these

to say that an object becomes electrically polarized means that: a) its internal electric field is zero b) it is electrically charged c) its charges have been rearranged d) it is only partially conducting e) none of the above

c) its charges have been rearranged

an uncharged pith ball is suspended by a nylon fiber. When a positively-charged rubber rod is brought nearby, the pith ball: a) moves away from the rod b) is unaffected c) moves toward the rod d) none of the above

c) moves toward the rod

rub electrons from your hair with a comb and the comb becomes: a) positively charged b) discharged c) negatively charged

c) negatively charged

before a thunder storm, clouds in the sky likely become: a) conducting b) grounded c) polarized d) a field-free region

c) polarized

a negatively-charged rod is held near an aluminum can that rests on a dry wood table. If you momentarily touch the opposite side of the can with your finger, the can becomes: a) partially discharged b) completely discharged c) positively charged d) negatively charged e) none of the above

c) positively charged

two charged particles repel each other with a force F. if the charge of one of the particles is doubled and the distance between them is also doubled, then the force will be: a) 2 F b) F/4 c) F d) F/2 e) none of the above

d) F/2

electric potential, measured in volts, is the ratio of electric energy to the amount of electric: a) resistance b) voltage c) current d) charge e) none of the above

d) charge

if you rub an inflated balloon against your hair and place the balloon against the wall it will stick to the wall, illustrating: a) Coulomb's law b) conduction and insulation c) voltage d) charge polarization

d) charge polarization

to say that electric charge is conserved means that no case has ever been found where: a) the total quantity of charge on an object has increased b) quantity of negative charge on an object exactly balances positive charge c) the total charge on an object has changed d) net charge has been created or destroyed e) none of the above

d) net charge has been created or destroyed

particle A has twice the charge of nearby particle B. compared to the force on particle A, the force on particle B is: a) four times as much b) half as much c) twice as much d) the same e) none of the above

d) the same

it is said that electric charge is quantized, which means that the charge on an object: a) will interact with neighboring electric charges b) is sometimes positive c) may occur in an infinite variety of quantities d) can be neither created nor destroyed e) is a whole-number multiple of the charge of one electron

e) is a whole-number multiple of the charge of one electron

a main difference between gravitational and electric forces is that electrical forces: a) attract b) obey the inverse-square law c) are weaker d) act over shorter distances e) repel or attract

e) repel or attract