Physics 2 Midterm
A system of 1728 particles, each of which is either an electron or a proton, has a net charge of +3.552 x 10-17 C. What is the mass of this system? A) 1.629 x 10-24 kg B) 222.0 kg C) 1.574 x 10-27 kg D) 2.886 x 10-24 kg
A) 1.629 x 10-24 kg
A circular coil of wire has a radius of 6.30 cm and has 215 turns of wire that carries 5.90 A of current. What is the magnetic field at the center of the coil? A) 12.7 mT B) 6.33 mT C) 58.8 μT D) 1 x 104 T
A) 12.7 mT
A three-way lightbulb can produce 30 W, 50 W, or 75 W of power at 60 V. What is the resistance of the lightbulb in the 75 W case? A) 48 ohms B) 60 ohms C) 75 ohms D) 1.25 ohms
A) 48 ohms
A 8.45-μC particle with a mass of 6.15 x 10-5 kg moves perpendicular to a 0.493-T magnetic field in a circular path of radius 34.1 m. How much time will it take for the particle to complete one orbit? A) 92.7 s B) 0.0927 s C) 9.27 s D) 927 s
A) 92.7 s
Two charges of +3.5 micro-C are placed at opposite ends of a meterstick. Where on the meterstick could a free proton be in electrostatic equilibrium? A) At the 0.5 m mark. B) At either the 0 m or 1 m marks. C) At the 0.35 m mark. D) Nowhere on the meterstick.
A) At the 0.5 m mark.
The direction of the magnetic force exerted on a charged object is ALWAYS (choose ALL that apply) A) perpendicular to the magnetic field vector (field direction). B) in a direction that makes the velocity and field vectors align. C) perpendicular to the velocity vector (direction of motion). D) along the magnetic field vector (field direction). E) along the velocity vector (direction of motion).
A) perpendicular to the magnetic field vector (field direction). C) perpendicular to the velocity vector (direction of motion).
If the charge on a capacitor is doubled, the energy stored in the capacitor is A) quadrupled. B) doubled. C) tripled. D) unchanged.
A) quadrupled.
A 100-W lightbulb operates on a potential difference of 120 V. Find the resistance of the bulb. A) 144 Ω B) 12 Ω C) 120 Ω D) 0.007 Ω
A) 144 Ω
How would you connect multiple batteries in order to get the biggest possible voltage? A) Put all of the batteries in series. B) Put some in parallel and some in series. C) It does not matter how you combine them. D) Put all of the batteries in parallel.
A) Put all of the batteries in series.
An object with a charge of +6.3 μC and a mass of 0.073 kg experiences an upward electric force, due to a uniform electric field, equal in magnitude to its weight. If the electric charge on the object is reduced by one-third while its mass remains the same, find the direction and magnitude of its acceleration. A) down at 6.5 m/s2 B) up at 4.9 m/s2 C) up at 9.8 m/s2 D) down at 4.9 m/s2 E) up at 6.5 m/s2 F) down at 9.8 m/s2
A) down at 6.5 m/s2
When charging a capacitor in an RC circuit, you expect A) the current to decrease with time. B) the current to increase with time. C) the current to stay constant.
A) the current to decrease with time.
The velocity selector in a mass spectrometer utilizes A) magnetic fields only. B) electric fields only. C) neither electric nor magnetic fields. D) electric and magnetic fields.
B) The negative charged particle would turn to the left..
(T/F): The resistivity and conductivity have no connection to each other.
False
On average, an electric water heater (4.5 kW) operates for 1.5 hours each day. If the cost of electricity is $0.20/kWh, what is the cost of operating the heater during a 14-day period? A) $12.60 B) $40.50 C) $18.90 D) $0.90
C) $18.90
A silver wire is 0.3 m long and has a diameter of 0.05 cm. What is the resistance of the wire? A) 6.1x10^(-3) ohms B) 6.1x10^(-7) ohms C) 2.4x10^(-2) ohms D) 1.6x10^(-8) ohms
C) 2.4x10^(-2) ohms
By convention, the direction of an electric field at any point in space is determined by the direction of the electric force on a A) negative charge. B) neutral charge. C) positive charge.
C) positive charge.
What is the voltage across ten 2.0 V batteries when they are connected in parallel? A) 20 V B) 5.0 V C) 10 V D) 2.0 V
D) 2.0 V
Electric fields are vector quantities. Which of the following descriptions is correct? A) Positive charges have electric field vectors that point TOWARDS the charge B) Negative charges have electric field vectors that point AWAY FROM the charge C) The sign of the charge has nothing to do with the field direction. D) Positive charges have electric field vectors that point AWAY FROM the charge.
D) Positive charges have electric field vectors that point AWAY FROM the charge.
An aluminum wire is 1.3 m long and has a diameter of 0.05 cm. What is the resistance of the wire? A) 0.18 Ω B) 0.045 Ω C) 9.0 x 10-5 Ω D) 2.65 x 10-8 Ω E) 5.3 x 10-5 Ω
A) 0.18 Ω
(T/F): The units of the time constant are ohm-farad. One ohm-farad equals one second.
True
A portable CD player operates with a current of 20 mA at a potential difference of 6.2 V. What is the power usage of the player? A) 0.124 W B) 124 W C) 12.4 W D) 0.124 V E) 1.24 V
A) 0.124 W
A charge of +3q sits at the origin. A charge of -5q sits on the x-axis at the 1.00 m mark. Given that q=4.11 x 10-9 C, at what location on the x-axis is the electric potential zero? A) 0.375 m B) 0.500 m C) 0.625 m D) 0.125 m
A) 0.375 m
A parallel plate capacitor has plates with an area of 0.019 m2 and a separation of 0.72 mm. The space between the plates is filled with a dielectric whose dielectric constant is 2.4. What is the potential difference between the plates when the charge on the capacitor plates is 5.8 μC? A) 1.0 x 104 V B) 1.0 x 10-4 V C) 2.4 x 104 V D) 1.0 x 107 V
A) 1.0 x 104 V
A cell membrane is 8.7 nm thick and has an electrical resistivity of 1.3 x 107 Ωm. If the potential difference between the inner and outer surfaces of a cell membrane is 63 mV, how much current flows through a circular patch of membrane with radius 1.0 μm? A) 1.8 x 10-12 A B) 5.6 x 10-13 A C) 1.3 x 10-5 A D) 1.2 x 10-18 A
A) 1.8 x 10-12 A
A proton has an initial speed of 4.90 x 105 m/s. What potential difference is required to bring the proton to rest? A) 1250 V B) -1250 V C) 2.00 x 10-16 V D) -2.00 x 10-16 V E) zero
A) 1250 V
A solenoid with 300 turns per centimeter has an iron core with a relative permeability of 100. The solenoid carries a current of 5.0 A. What is the magnetic field at the central axis of the solenoid? A) 19 T B) 30 T C) 1.9 T D) 0.19 T
A) 19 T
The resistor in an RC circuit has a resistance of 110 Ω and a time constant of 1.9 ms. Calculate the current in the circuit 7.6 ms after the switch is closed. Assume that the capacitor is initially uncharged and that the emf of the battery is 12.0 V. A) 2 mA B) 110 mA C) 27.5 mA D) 40 mA
A) 2 mA
Two point charges, the first with a charge of +4.47 x 10-6 C and the second with a charge of +1.86 x 10-6 C, are separated by 17.4 mm. What is the magnitude of the electrostatic force experienced by charge 2? A) 247 N B) 2.47 x 10-4 N C) 103 N D) 2.74 x 10-8 N
A) 247 N
What is the magnitude of the magnetic force exerted on a 4.67-m length of wire carrying a current of 2.38 A perpendicular to a magnetic field of 0.385 T? A) 4.28 N B) 0.916 N C) 11.1 N D) 1.80 N
A) 4.28 N
An object with charge -Q is placed in an electrically neutral metal cup (without touching the cup). Which of the following best describes the situation? (multiple) A) The electric field in the metal of the cup is zero, the charge in the metal is zero, and the surface charge is -Q. B) The electric field in the metal of the cup is defined by +Q, the charge in the metal is -Q, and there is no surface charge. C) The electric field in the metal of the cup is zero, the charge in the metal is zero, and the surface charge is +Q D) The electric field in the metal of the cup is defined by -Q, the charge in the metal is +Q, and there is no surface charge. E) The electric field in the metal of the cup is zero, the charge in the metal is -Q, and there is no surface charge.
A) The electric field in the metal of the cup is zero, the charge in the metal is zero, and the surface charge is -Q. C) The electric field in the metal of the cup is zero, the charge in the metal is zero, and the surface charge is +Q
Imagine two sets of charges; set A is made up of two electrons, and set B is made up of two protons. The two sets of charges are far from each other so they cannot affect one another. Which of the following is true? A) The electric forces in both cases are repulsive. B) The electric forces in both cases are attractive. C) The electric forces in set A are attractive, but the forces in set B are repulsive. D) The electric forces in set A are repulsive, but the forces in set B are attractive.
A) The electric forces in both cases are repulsive.
You rub a balloon on your hair and it gains a net negative charge. Which of the following statements is true? A) The negative charge gained by the balloon has been lost by your hair, so the net change in the charge of the hair-balloon system is zero. B) The charge gained by the balloon was created by friction, so the net change in the charge of the hair-balloon system is negative. C) The charge gained by the balloon was created by induction, so the net change in the charge of the hair-balloon system is negative. D) The negative charge gained by the balloon is equal to the negative charge left on your hair, so the net change in the charge of the hair-balloon system is negative.
A) The negative charge gained by the balloon has been lost by your hair, so the net change in the charge of the hair-balloon system is zero.
How are electric potential difference (voltage) and electric potential energy related? A) The voltage is the potential energy per unit positive charge. B) There is no relationship. C) The potential energy is the voltage per unit positive charge. D) The voltage is the electric field value divided by a positive charge.
A) The voltage is the potential energy per unit positive charge.
If you want to create a working battery, which one of the following options MUST occur? A) There must be a larger excess of electrons at one electrode than at the other. B) There must be equal numbers of electons at each electrode. C) There must be the same electric potential at each electrode. D) There must be no voltage between the electrodes.
A) There must be a larger excess of electrons at one electrode than at the other.
Electric potential is A) a scalar. B) the same as electric force. C) the same as electic field. D) a vector.
A) a scalar.
In a closed circuit, the movement of electrons is best described as A) basically random movement with a slow drift in the direction opposing the current. B) basically random movement with a slow drift in the direction of the current. C) very fast straight-line motions in the direction of the current. D) very fast straight-line motions in the direction opposing the current.
A) basically random movement with a slow drift in the direction opposing the current.
We can conserve energy by (choose all answers that are correct) A) following Dad's advice to "turn off the light when you're not in the room". B) using lightbulbs that use less electrical power while producing the same amount of light. C) choosing appliances that minimize power consumption. D) increasing the efficiency of all of our appliances and electrical devices.
A) following Dad's advice to "turn off the light when you're not in the room". B) using lightbulbs that use less electrical power while producing the same amount of light. C) choosing appliances that minimize power consumption. D) increasing the efficiency of all of our appliances and electrical devices.
An ideal voltmeter A) has infinite resistance. B) has zero resistance. C) can have any resistance value.
A) has infinite resistance.
The magnetic field at the center of a current carrying loop (choose ALL answers that apply) A) increases in magnitude as the current increases. B) points in a direction perpendicular to the plane that contains the loop. C) points towards the center of the loop. D) increases in magnitude as the radius of the loop increases.
A) increases in magnitude as the current increases. B) points in a direction perpendicular to the plane that contains the loop.
If the potential increases most rapidly in the positive y-direction, the electric field points in the A) negative y-direction. B) positive y-direction. C) negative x-direction. D) positive x-direction.
A) negative y-direction.
If you are charging an initially uncharged capacitor in an RC circuit, the voltage of the capacitor A) starts at zero and increases to the battery voltage. B) remains at zero always. C) starts at the battery voltage and decreases to zero. D) always remains equal to the battery voltage.
A) starts at zero and increases to the battery voltage.
If the distance between two equal positive charges doubles, A) the magnitude of the electric force decreases by a factor of 4. B) the magnitude of the electric force decreases by a factor of 2. C) the magnitude of the electric force increases by a factor of 4. D) the magnitude of the electric force does not change.
A) the magnitude of the electric force decreases by a factor of 4.
An equipotential surface is A) the set of locations where the electric potential is constant. B) the same as the direction of the electric field. C) the amount of work done in moving a charge. D) always perpendicular to a charge distribution.
A) the set of locations where the electric potential is constant.
Two point charges lie on the x axis. A charge of -2.3 x 10-6 C is at x=-5 cm, and a charge of +9.2 x 10-6 C is at x=12 cm. At what position x would a third positive charge be in equilibrium? A) x=-22 cm B) x=+22 cm C) x=0 cm D) x=-17 cm E) x=+17 cm
A) x=-22 cm
A 200-ohm resistor is placed in a circuit with four identical batteries connected in series. If the resistor draws 4.0 A, what is the terminal voltage of each battery? A) 1600 V B) 200 V C) 75 V D) 100 V
B) 200 V
In a flashing neon light circuit, a time constant of 1.2 s is desired. If you have a 3.0 micro-farad capacitor, what resistance should you use in the circuit? A) 3.6x10^(-6) ohms B) 4.0x10^(5) ohms C) 2.5x10^(-6) ohms D) 4.0x10^(5)
B) 4.0x10^(5) ohms
In a physics lab, a student discovers that the magnitude of the magnetic field in a specific location near a long wire is 0.3 micro-T. If the wire carries a current of 10 A, what is the distance from the wire to that location? A) 0.67 m B) 6.7 m C) 0.25 m D) 0.15 m
B) 6.7 m
Imagine you are measuring the electric field of a negative point charge. When you place your field measuring instrument 1 m away from the charge you measure a magnitude of 2 N/C. What does your instrument read when you are 0.5 m away? A) 2 N/C. B) 8 N/C. C) 4 N/C. D) 0.5 N/C.
B) 8 N/C.
Object A has a net charge of +Q. Object B has a net charge of +2Q. A positive test charge is first brought 1 m from object A. Object A is removed and the same test charge is brought 2 m from object B. Which of the following correctly describes the relative magnitudes of the electric fields experienced by the test charge? A) The field due to object B is twice that due to object A. B) Answer The field due to object A is twice that due to object B. C) The field due to object A is four times that due to object B. D) The field due to object B is four times that due to object A.
B) Answer The field due to object A is twice that due to object B.
Look at Fig. 19.10(b). If the charge q3 moved closer to charge q1 along the dashed line, A) the net force vector would gain an upward vertical component and its horizontal component would decrease. B) Answer the net force vector would gain an upward vertical component and its horizontal component would increase. C) the net force vector would remain unchanged. D) the net force vector would gain a downward vertical component and its horizontal component would increase.
B) Answer the net force vector would gain an upward vertical component and its horizontal component would increase.
An electrically neutral object (like a balloon) A) cannot be subjected to electric forces because it is neutral. B) can be subjected to electric forces due to polarization. C) can be subjected to electric forces only if it gains a net negative charge. D) can be subjected to electric forces only if it gains a net positive charge.
B) can be subjected to electric forces due to polarization.
Three resistors with values of 7.5 ohms, 9.0 ohms, and 20 ohms are connected in series in a circuit with a 12-volt battery. What is the current in each resistor? A) current in resistor 1=1.6 A, current in resistor 2=1.6 A, current in resistor 3=1.6 A B) current in resistor 1=0.33 A, current in resistor 2=0.33 A, current in resistor 3=0.33 A. C) current in resistor 1=3.5 A, current in resistor 2=3.5 A, current in resistor 3=3.5 A D) current in resistor 1=1.6 A, current in resistor 2=1.3 A, current in resistor 3=0.6 A
B) current in resistor 1=0.33 A, current in resistor 2=0.33 A, current in resistor 3=0.33 A.
The resistance of something A) depends only on its geometry. B) depends on its resistivity and its geometry. C) is a fundamental property of a material. D) depends only on its resistivity.
B) depends on its resistivity and its geometry.
Magnetic fields can be caused by A) magnetic currents. B) electric currents. C) any moving object, regardless of charge. D) stationary charges.
B) electric currents.
As the current increases, the electric power provided by a battery A) decreases first, then increases. B) increases. C) decreases. D) stays the same.
B) increases.
Capacitors connected in series... (Choose ALL answers that are correct) A) must have the same voltages. B) must have the same charges. C) act like one capacitor with a capacitance equal to the sum of the individual capacitances. D) act like one capacitor with an inverse capacitance equal to the sum of the inverses of the individual capacitances.
B) must have the same charges. D) act like one capacitor with an inverse capacitance equal to the sum of the inverses of the individual capacitances.
The resistance in a conductor like copper increases with length because A) the electrons can be absorbed more easily. B) the electrons have more opportunity to bounce off of atoms and not participate in the overall flow. C) the electric force decreases with increasing distance. D) they have farther to go without colliding with atoms.
B) the electrons have more opportunity to bounce off of atoms and not participate in the overall flow.
A parallel plate capacitor has a capacitance of 2.0 micro-F with air between the plates. The capacitor is connected to a 9.0-volt battery and charged. The battery is then removed. When a dielectric is placed between the plates, a potential difference of 7.5 V is measured across the plates. What is the dielectric constant of the material? A) 1.7 B) 0.83 C) 1.2 D) 1.0
C) 1.2
A 12-V battery is connected to four capacitors in series. The capacitors have the following capacitances: 9 μF, 12 μF, 32 μF, and 42 μF. Find the voltage across the 32 μF capacitor. A) 4 V B) 12 V C) 1.5 V D) 0.375 V
C) 1.5 V
Kirchoff's junction theorem is a restatement of which of the following physical laws? A) Conservation of momentum. B) Conservation of mass. C) Conservation of charge. D) Conservation of energy.
C) Conservation of charge.
How are electric potential difference (voltage) and electric potential energy related? A) The potential energy is the voltage per unit positive charge. B) The voltage is the electric field value divided by a positive charge. C) The voltage is the potential energy per unit positive charge. D) There is no relationship.
C) The voltage is the potential energy per unit positive charge.
In a laboratory, two wires lay next to each other on a bench. Wire A is twice as long as wire B. An experiment causes the two wires to have the same current flowing through them. The wires both exist in the magnetic field of the Earth. Which of the following correctly describes the magnetic force magnitudes experienced by the wires? A) Wire B feels twice the force of wire A. B) The wires feel the same force. C) Wire A feels twice the force of wire B.
C) Wire A feels twice the force of wire B.
Relative to the vacuum value, a dielectric always A) decreases the capacitance. B) doubles the capacitance. C) increases the capacitance. D) leaves the capacitance unchanged.
C) increases the capacitance.
Two particles with the same net charge come through a velocity selector and enter the region of a mass spectrometer with only a magnetic field. If particle A lands twice as far from the entrance as particle B, then A) particle B has twice the mass of particle A. B) we need to know the magnetic field strength in order to determine which one is more massive. C) particle A has twice the mass of particle B. D) we need to know the speed in order to determine which one is more massive.
C) particle A has twice the mass of particle B.
Imagine an RC circuit that contains a fully charged capacitor. If the capacitor is discharged, A) the capacitor voltage is largest and the circuit current is smallest at the start of the discharge process. B) the capacitor voltage and circuit current are smallest at the start of the discharge process. C) the capacitor voltage and circuit current are largest at the start of the discharge process. D) the capacitor voltage is smallest and the circuit current is largest at the start of the discharge process.
C) the capacitor voltage and circuit current are largest at the start of the discharge process.
The torque on a current-carrying loop is maximum when A) the magnetic moment is zero. B) the magnetic moment points in the direction of the current. C) the magnetic moment is perpendicular to the magnetic field direction. D) the magnetic moment is along the magnetic field direction.
C) the magnetic moment is perpendicular to the magnetic field direction.
For a given circuit voltage and 10 resistors, which situation provides the largest circuit current? A) Pairs of resistors alternating between series and parallel. B) All of the resistors in series. C) Half the resistors in series, half in parallel (order doesn't matter). D) All of the resistors in parallel.
D) All of the resistors in parallel.
Object A has a net charge of +Q. Object B has a net charge of +2Q. A positive test charge is first brought 1 m from object A. Object A is removed and the same test charge is brought 1 m from object B. Which of the following correctly describes the relative magnitudes of the electric fields experienced by the test charge? A) The field due to object A is four times that due to object B. B) The field due to object A is twice that due to object B. C) The field due to object B is four times that due to object A. D) The field due to object B is twice that due to object A.
D) The field due to object B is twice that due to object A.
When resistors are connected in parallel, the currents through each resistor A) are zero in all resistors but one. B) are all equal. C) are different with the largest current flowing through the largest resistor. D) are different with the largest current flowing through the smallest resistor.
D) are different with the largest current flowing through the smallest resistor.
In order to measure the voltage drop due to a resistor in a circuit, a voltmeter should be A) connected in series, or "in-line", with the resistor. B) connected only to the wire through which the current leaves the resistor. C) connected to the battery or voltage source. D) connected in parallel, or "across", the resistor.
D) connected in parallel, or "across", the resistor.
The magnetic force on a current-carrying wire is greatest when the current is A) due to positive charges only. B) parallel to the magnetic field direction. C) at a 45-degree angle to the magnetic field direction. D) perpendicular to the magnetic field direction.
D) perpendicular to the magnetic field direction.
The rear window defogger on your car works by Joule heating. If the current through those wires doubles, the heating power A) stays the same. B) halves. C) doubles. D) quadruples.
D) quadruples.
(T/F): With a battery, direct currents can sometimes flow from the anode to the cathode, but at other times they flow in the opposite direction.
False
(T/F): If the amount of charge is fixed, a capacitor can store more energy when the voltage is larger.
True
(T/F): In a Kirchoff loop, if the loop direction and current direction coincide for a resistor, the voltage is considered to be negative.
True
(T/F): Kirchoff's loop theorem states that the sum of ALL potential differences (drops and sources) around a closed loop must be zero.
True
(T/F): Negative charges, when allowed to move, go towards regions where the electric potential is high.
True
(T/F): You can increase the strength of a solenoid's magnetic field by inserting an iron core inside the coils of the solenoid.
True
IT/F): The net force on a current-carrying loop in a uniform magnetic field is zero.
True
A solid conducting sphere is surrounded by a thick, spherical conducting shell. A total charge of -Q is initially placed and released at the center of the inner sphere. After equilibrium is reached, how much charge is on the outer surface of the shell? A) No charge B) -Q C) +Q
B) -Q
A 4.0-meter length of straight wire carries a current of 15 A in a uniform magnetic field of 500 micro-T whose field lines make an angle of 45-degrees with the current direction. Find the force on the wire. A) 2.1x10^(-2), perpendicular to the paper B) 2.1x10^(-2) N, perpendicular to the paper C) 3.0x10^(-2) N, parallel to the current direction D) 2.1x10^(-2) N, parallel to the magnetic field vector
B) 2.1x10^(-2) N, perpendicular to the paper
In a flashing neon sign display, the resistance is 5 million ohms, and the time constant is 6.0 sec. Suppose you want a time constant of 3.0 sec. A) 5 million ohms B) 2.5 million ohms C) 15 million ohms D) 10 million ohms
B) 2.5 million ohms
A 6.0-volt battery is connected to a parallel plate capacitor with plate areas of 0.3 meters-squared each and a plate separation of 10 mm. How much energy is stored in the capacitor? A) 8.2x10^(-10) J B) 4.8x10^(-9) J C) 1.6x10^(-9) J D) 4.9x10^(-9)
B) 4.8x10^(-9) J
A positively charged particle enters the magnetic field region of a mass spectrometer and turns to the right. What would happen to an equal-mass particle with a negative charge of equal magnitude? A) The negatively charged particle would follow the same path, because it has the same mass. B) The negative charged particle would turn to the left..
B) The negative charged particle would turn to the left..
According to Ohm's law, a graph of voltage (y-axis) versus resistance (x-axis) would look like A) a straight line with a slope equal to the resistance value. B) a straight line with slope equal to the current value. C) a straight horizontal line (constant value). D) a straight line with slope equal to the inverse of the current value.
B) a straight line with slope equal to the current value.
In a parallel plate situation, the voltage is 60 V. If the electric potential value at the negative plate is 60 V, then A) the electric potential value at the positive plate is -60 V. B) the electric potential value at the positive plate is 120 V. C) the electric potential value at the positive plate is 0 V. D) the electric potential value at the positive plate is 60 V.
B) the electric potential value at the positive plate is 120 V.
In a Kirchoff loop, the voltage of a battery is treated as positive if the loop is traversed from A) either direction. B) the negative to positive terminal. C) the positive to negative terminal.
B) the negative to positive terminal.
In order to "jump start" a dead car battery, the anodes and cathodes of the dead battery and a good battery are connected in parallel with jumper cables. In this situation, A) the total voltage available to the dead car is twice as large as that of the good battery. B) the total voltage available to the dead car is the same as that of the good battery. C) the total voltage available to the dead car is half that of the good battery. D) the total voltage available to the dead car is 4 times as large as that of the good battery.
B) the total voltage available to the dead car is the same as that of the good battery.
A glass rod rubbed with silk acquires a charge of +7.0x10^(-9) C. How much mass is transferred from the rod? A) 4.0x10^(-20) B) 4.4x10^(10) C) 4.0x10^(-20) kg D) -4.0x10(-20) kg
C) 4.0x10^(-20) kg
Two parallel plates are a distance d apart with a constant electric field E between them. An electron with charge q is released from a point near the negative plate and is made to travel at constant velocity. Which of the following is correct? A) The work done by the electric field as the charge moves is -qEd. B) The work done by the electric field as the charge moves is zero. C) The work done by the electric field as the charge moves is +qEd.
C) The work done by the electric field as the charge moves is +qEd.
In order to measure the current passing through a resistor, an ammeter should A) have a resistance equal to that of the resistor being measured. B) be connected in parallel, or "across", the resistor C) be connected in series, or "in-line", with the resistor D) have a very large internal resistance
C) be connected in series, or "in-line", with the resistor
For a fixed voltage, you can increase the power by A) increasing the resistance. B) not changing the resistance. C) decreasing the resistance.
C) decreasing the resistance.
By convention, magnetic field lines A) enter at N poles and exit from S poles. B) can either enter or exit N poles and S poles. C) exit from N poles and enter at S poles. D) don't tell us anything about the direction of magnetic fields.
C) exit from N poles and enter at S poles.
Compared to solenoid B, solenoid A has ten times the number of turns per meter. The largest magnetic field belongs to A) neither, they are the same. B) neither, they are both zero. C) solenoid A. D) solenoid B.
C) solenoid A.
For resistors in parallel, A) the currents through each resistor are equal. B) the individual voltage drops across the resistors add up to the total voltage. C) the voltages across each resistor are equal. D) the current only flows through one resistor.
C) the voltages across each resistor are equal.
Two objects with opposite charges are fixed in place (they cannot move). If the charge on the negative object doubles and the positive object's charge remains the same, A) then the force doesn't change because the objects are fixed. B) only the force on the positive charge increases by a factor of 2. C) then the force on both charges increases by a factor of 2. D) only the force on the negative charge increases by a factor of 2.
C) then the force on both charges increases by a factor of 2.
If a current flows to the right in a wire that is in a magnetic field that points into your computer screen, the direction of the force on the wire is A) out of the screen towards you. B) into the screen away from you. C) towards the top of the screen. D) towards the bottom of the screen.
C) towards the top of the screen.
A charged object is brought near a neutral electroscope. If the leaves separate, A) you know that the object has a net negative charge. B) you know that the object is electrically neutral. C) you know that the object has a net electric charge. D) you know that the object has a net positive charge.
C) you know that the object has a net electric charge.
Determine the value of the potential 3.50 mm from the positive plate of a pair of parallel plates separated by 12.0 mm and connected to a 18.0-volt battery. A) 8.50 V B) 18.0 V C) 5.25 V D) 12.8 V
D) 12.8 V
A proton travels at a speed of 3.0x10^(6) m/s through a uniform magnetic field whose magnitude is 8.0x10^(-3) T. What is the magnitude of the magnetic force on the proton if its velocity vector and the magnetic field vector are perpendicular? A) 3.8x10^(-18) N B) 0.0 N C) 3.8x10^(-15) D) 3.8x10^(-15) N
D) 3.8x10^(-15) N
Capacitance increases as A) the charge increases and/or the voltage increases. B) the charge decreases and/or the voltage decreases. C) the charge decreases and/or the voltage increases. D) the charge increases and/or the voltage decreases.
D) the charge increases and/or the voltage decreases.
(T/F): An ideal ammeter has a voltage drop across it.
False
(T/F): Connecting resistors in series always decreases the total resistance.
False
(T/F): Electric field lines are drawn parallel to equipotentials.
False
(T/F): If two current-carrying wires are placed parallel to one another, but the currents run in opposite directions, the wires will attract one another.
False
(T/F): In reality, magnetic poles can be found as isolated, single objects.
False
(T/F): The only way for an object to have an electric charge is to have an excess of electrons.
False
