Test 2 Flashcards
Alternating current is normally produced by a
a) generator
b) battery
c) both
d) neither
a) generator
the unit of resistance is the
a) coulomb
b) ohm
c) volt
d) joule
e) amp
b) ohm
the electric charge on all electrons
a) vary from atom to atom
b) vary from ion to ion
c) are identical
c. are identical
the source of electrons lighting an incandescent light bulb is
a. atoms in the light bulb filament
b. the source of voltage
c. the electric outlet
d. the power company
e. the wire leading to the lamp
a. atoms in the lightbulb filament
an electron and a proton
a. attract or repel depending on distance
b. repel each other
c. attract each other
c. attract each other
the current in the wires of an AC
a. changes direction
b. is nonexistent
c. remains relatively constant
d. changes via the inverse square law
e. none of the above
a. changes direction
maximum magnetic force on a current-carrying wire occurs when the wire is
a. in the same direction as the magnetic field
b. at an angle other than 90degrees to the magnetic field direction
c. opposite to the magnetic field direction
d. perpendicular to the magnetic field direction
e. none of the above
d. perpendicular to the magnetic field direction
the nucleus of an atom is charged
a. negatively
b. positively
c. both
d. none
b. positively
a difference between an insulator and a conductor is that a conductor has more
a. protons than electrons
b. faster moving molecules
c. electrons than protons
d. energy than an insulator
e. none of the above
e. none of the above
when a person experiences an electric shock, the origin of the electrons compromising the shock is
a. the ground
b. likely a faulty lamp
c. the person’s own body
d. a power plant
e. the electric field in the air
c. the person’s own body
the electric force between charges depends on
a. magnitude of electric charges
b. seperation distance between electric charges
c. both
d. neither
c. both
unlike electric charges, magnetic poles cannot be
a. observed
b. located
c. separated
c. separated
when a steady voltage is applied to one-half as much resistance, the current is
a. is quadrupled
b. is doubled
c. remains the same
d. is half
b. is doubled
if you strip electrons from an atom, the atom becomes
a. negatively charged
b. positively charged
b. positively charged
the current in a conducting wire is composed of
a. electrons
b. protons
c. neutrons
d. all or any
a. electrons
when a current-carrying wire in a magnetic field experiences no force it is likely
a. parallel to the field lines
b. upside down relative to the field
c. overly insulated
d. all of the above
a. parallel to the field lines
to say that electric charge is conserved is to say that electric charge
a. may occur in an infinite variety of quantities
b. will interact with neighboring electric charges
c. can neither be created nor destroyed
d. is a whole-number multiple of the charge of one electron
c. can neither be created or destroyed
when the distance between two charges is halved, the electric force between the charges
a. doubles
b. quadruples
c. is half
d. is reduced by one-quarter
e. noen of the above
b. quadruples
two charged particles near each other are released. as they move, the coulomb’s law electric force on each particle increases. therefore, the particles have
a. not enough information
b. opposite kinds of charge
c. the same kind of charge
b. opposite kinds of charge
when a magnet is moved near a loop of wire
a. a voltage is induced in the wire
b. current is made to flow in the loop of wire
c. electromagnetic induction occurs
d. all of the above
d. all of the above
the number of protons in the nucleus of an electrically neutral atom is equal to the number of
a. electrons that surround the nucleus
b. neutrons in the nucleus
c. both
d. neither
a. electrons that surround the nucleus
electric potential energy is measured in units of
a. volts
b. watts
c. joules
d. amperes
e. any or all
c. joules
a device that converts EPE to KE is a
a. transformer
b. motor
c. magnet
d. generator
e. none of the above
b. motor
a pair of positively charged plastic straws tend to
a. repel each other
b. neutralize each other
c. attract each other
a. repel each other
break a bar magnet in half and each half is
a. no longer magnetized
b. a magnet with a single pole
c. a magnet with a N and S pole
c. a magnet with a N and S pole
compared to the mass of a proton, the mass of the electron is
a. very much less
b. identical
c. greater
a. very much less
an ampere is a unit of electric
a. resistance
b. current
c. energy
d. all of the above
e. none of the above
b. current
a magnetic field exists in a current-carrying coil of wire
a. if it contains a piece of iron
b. only if the current changes
c. with or without a contained piece of iron
c. with or without a piece of iron
a negatively charged balloon touching a wooden wall
a. pulls positive charge on the wall surface toward it
b. polarizes molecules in the wall
c. pushes negative charge in the wall away from it
d. all of the above
d. all of the above
Like kinds of magnetic poles repel while unlike kinds of magnetic poles
a. attract
b. repel also
c. may attract or repel
a. attract
when the voltage across a steady resistance is doubled, the current
a. is doubled
b. is quadrupled
c. is half
d. remains the same
a. is doubled
electrons will flow in an electric circuit when
a. there is a voltage
b. electric devices in the circuit are not defective
c. electric resistance is low
d. the circuit is grounded
a. there is a voltage
when you remove electrons from a metal cup, the cup becomes
a, negatively charged
b. positively charged
c. ionized
b. positively charged
electric potential is measured in units of
a. joules
b. amperes
c. volts
d. watts
e. any or all
c. volts
to say that an object is electrically polarized is to say
a. it is to some degree magnetic
b. it is only partially conducting
c. its charges have been separated
d. its internal EPE is zero
e. it is electrically charged
c. its charges have been separated
the electric force between charges is strongest when the charges are
a. close together
b. far apart
c. neither
a. close together
to say a current is DC is to say that current in the circuit
a. is parallel to the connecting wires
b. alternates only slowly
c. has a single direction
c. has a single direction
a device that converts KE to EPE is a
a. motor
b. generator
c. transformer
d. magnet
e. none of the above
b. generator
a 100N box and a 200N box are hoisted the same distance. raising the heavier box requires
a. twice as much work
b. less work
c. four times as much work
d. as much work
e. more than four times as much work
a. twice as much work
stretch a copper wire so that it is thinner and the resistance between its ends
a. remains unchanged
b. decreases
c. increases
c. increases
charge carriers in a metal are electrons rather than protons because electrons are
a. smaller
b. loosely bound
c. negative
d. all
e. none
b. loosely bound
electrical resistance is greater for
a. wet skin
b. dry skin
c. both are the same
b. dry skin
an electromagnet consists of a
a. bar magnet that carries an electric current
b. coil of wire
c. current-carrying coil with a piece of iron inside
c. current-carrying coil with a piece of iron inside
when the current in a wire is reversed, the direction of the surrounding magnetic field
a. also reverses
b. remains steady
c. collapses
a. also reverses
the source of all magnetism is
a. tiny bits of iron
b. aligned atoms
c. moving electric charge
d. ferromagnetic materials
c. moving electric charge
