final study packet
D) 2L , L , 2L/3
Consider a pipe of length L that is open at both ends. What are the wavelengths of the three lowest-pitch tones produced by this pipe? A) 4L , 2L , L B) 4L , 4L/3, 4L/5 C) 2L , L , L/2 D) 2L , L , 2L/3
D) 50 m
Crests of an ocean wave pass a pier every 9.0 s. If the waves are moving at 5.6 m/s, what is the wavelength of the ocean waves? A) 25 m B) 43 m C) 58 m D) 50 m
A) an odd number of half-wavelengths.
Two beams of coherent light start out at the same point in phase and travel different paths to arrive at point P. If the maximum destructive interference is to occur at point P, the two beams must travel paths that differ by A) an odd number of half-wavelengths. B) a whole number of half-wavelengths. C) a whole number of wavelengths
B) 16Q
Two horizontal pipes are the same length, but pipe B has twice the diameter of pipe A. Water undergoes viscous flow in both pipes, subject to the same pressure difference across the lengths of the pipes. If the flow rate in pipe A is Q = (change V)/(change t) what is the flow rate in pipe B? A) 4Q B) 16Q C) 2Q D) Q sqr rt 2 E) 8Q
D) 5.00 Hz
Two in-phase loudspeakers are some distance apart. They emit sound with a frequency of 536 Hz. A microphone is moved between the speakers along the line joining the two speakers with a constant speed of 1.60 m/s. What beat frequency is observed? The speed of sound in air is 343 m/s. A) 7.00 Hz B) 9.00 Hz C) 6.00 Hz D) 5.00 Hz E) 8.00 H
C) 24.0 uN/m
Two long parallel wires are 0.400 m apart and carry currents of 6.00 A and 8.00 A. What is the magnitude of the force per unit length that each wire exerts on the other wire? ( u0 = 4 pi × 10^-7 T x m/A) A) 38.0 uN/m B) 2.00 uN/m C) 24.0 uN/m D) 16.0 uN/m E) 5.00 uN/m
E) 5.0 × 10 -5 T
Two long parallel wires carry currents of 20 A and 5.0 A in opposite directions. The wires are separated by 0.20 m. What is the strength of the magnetic field midway between the two wires? ( u0 = 4 pie × 10 -7 T x m/A) A) 3.0 × 10 -5 T B) 4.0 × 10 -5 T C) 1.0 × 10 -5 T D) 2.0 × 10 -5 T E) 5.0 × 10 -5 T
B) 2190 Hz
Two loudspeakers placed 6.00 m apart are driven in phase by an audio oscillator having a frequency range from 1908 Hz to 2471 Hz. A point P is located 4.70 m from one loudspeaker and 3.60 m from the other speaker. At what frequency of the oscillator does the sound reaching point P interfere constructively? The speed of sound is 344 m/s. A) 2110 Hz B) 2190 Hz C) 2270 Hz D) 2420 Hz E) 2340 Hz
B) 0.30 A
Two resistors having resistances of 5.0 ohm and 9.0 ohm are connected in parallel. A 4.0-ohm resistor is then connected in series with the parallel combination. An ideal 6.0-V battery is then connected across the series-parallel combination. What is the current through the 9.0-ohm resistor? A) 0.53 A B) 0.30 A C) 0.83 A D) 0.67 A E) 0.35 A
E) current
For the graph shown in the figure, what physical quantity does the slope of the graph represent for ohmic material? A) resistivity B) 1/(resistivity) C) 1/(current) D) power E) current
A) The equivalent resistance is more than the largest resistance.
Four unequal resistors are connected in series with each other. Which one of the following statements is correct about this combination? A) The equivalent resistance is more than the largest resistance. B) The equivalent resistance is less than that of the smallest resistor. C) The equivalent resistance is less than that of the largest resistor. D) The equivalent resistance is equal to that of any one of the resistors. E) The equivalent resistance is equal to average of the four resistances
D) 1.60 × 10 -17 J
How much work must we do on an electron to move it from point A, which is at a potential of +50V, to point B, which is at a potential of -50 V, along the semicircular path shown in the figure? Assume the system is isolated from outside forces. ( e = 1.60 × 10 -19 C) A) -1.6 J B) 1.6 J C) -1.60 × 10 -17 J D) 1.60 × 10 -17 J E) This cannot be determined because we do not know the distance traveled.
C) 4.0 m/s
Ideal incompressible fluid flows through a 4.0-cm-diameter pipe at 1.0 m/s. There is a 2.0 cm diameter constriction in the line. What is the speed of the fluid in this constriction? A) 0.50 m/s B) 2.0 m/s C) 4.0 m/s D) 0.25 m/s
C) The gauge pressure does not change. E) The absolute (total) pressure increases by change p .
If atmospheric pressure increases by an amount change p , which of the following statements about the pressure in a lake is true? (There could be more than one correct choice.) A) The gauge pressure increases by change p . B) The absolute (total) pressure does not change. C) The gauge pressure does not change. D) The absolute (total) pressure increases, but by an amount less than change p . E) The absolute (total) pressure increases by change p .
E) impossible to determine based on the information given
If the electric potential at a point in space is zero, then the electric field at that point must be A) zero. B) negative. C) uniform. D) positive. E) impossible to determine based on the information given
C) 5.7 V
If the maximum voltage of an ac signal is 8.0 V, what is the rms value of this voltage? A) 4.0 V B) 6.2 V C) 5.7 V D) 2.8 V E) 16.0 V
C) 6.65 s
In 1851 Jean Bernard Leon Foucault demonstrated the rotation of the earth using a pendulum 11.0 m long, which was set up in the Paris Observatory. How long would it have taken for Foucault's pendulum to make one complete swing back to its starting point if g = 9.81 m/s 2 at the observatory? A) 1.79 s B) 2.58 s C) 6.65 s D) 5.63 s E) 2.12 s
C) It increases to 2.0 cm
In a double-slit experiment, it is observed that the distance between adjacent maxima on a remote screen is 1.0 cm. What happens to the distance between adjacent maxima when the slit separation is cut in half? A) It decreases to 0.25 cm. B) It decreases to 0.50 cm. C) It increases to 2.0 cm. D) It increases to 4.0 cm. E) None of these choices are correct
A) 4.5 mm
In a double-slit experiment, the slit separation is 2.0 mm, and two wavelengths, 750 nm and 900 nm, illuminate the slits. A screen is placed 2.0 m from the slits. At what distance from the central maximum on the screen will a bright fringe from one pattern first coincide with a bright fringe from the other? A) 4.5 mm B) 6.0 mm C) 1.5 mm D) 3.0 mm
D) 1.48 × 10 -5 m
In a two-slit experiment, a third-order bright fringe is observed at an angle of 6.80 ° away from the centerline. If the wavelength of light is 585 nm, how far apart are the two slits? A) 2.53 × 10 -5 m B) 2.12 × 10 -5 m C) 3.76 × 10 -5 m D) 1.48 × 10 -5 m E) 1.07 × 10 -5 m
C) reduced to one-half the original value.
In an RLC ac circuit, the values of the inductance and capacitance are both doubled. As a result of this change, the resonance frequency of the circuit is A) the same as before. B) reduced to one-fourth the original value. C) reduced to one-half the original value. D) four times the original value. E) twice the original value
A) when the magnitude of the acceleration is a minimum C) when the potential energy is a zero
In simple harmonic motion, when is the speed the greatest? (There could be more than one correct choice.) A) when the magnitude of the acceleration is a minimum B) when the displacement is a maximum C) when the potential energy is a zero D) when the magnitude of the acceleration is a maximum E) when the potential energy is a maximum
B) 180°
Light reflects off the surface of Lake Superior. What phase shift does it undergo? A) 90° B) 180° C) 270° D) 0° E) It does not undergo any phase shift
C) 0.90 m/s
Motor oil, with a viscosity of 0.25 N x s/m2 , is flowing through a tube that has a radius of 3.0 mm and is 1.0 m long. The drop in pressure over the length of the tube is 200 kPa. What is the average speed of the oil? A) 1.2 m/s B) 0.80 m/s C) 0.90 m/s D) 1.0 m/s E) 1.1 m/s
B) 2.78 × 10 4 N
One of the dangers of tornados and hurricanes is the rapid drop in air pressure that is associated with such storms. Assume that the air pressure inside of a sealed house is 1.02 atm when a hurricane hits. The hurricane rapidly decreases the external air pressure to 0.910 atm. What net outward force is exerted on a square window of the house that is 1.58 m on each side? (1.00 atm = 1.01 × 10 5 Pa) A) 3.28 × 10 5 N B) 2.78 × 10 4 N C) 3.14 × 10 4 N D) 2.92 × 10 5 N
D) 96 kV
A +4.0-uC and a -4.0-uC point charge are placed as shown in the figure. What is the potential difference between points A and B? (k = 9.0 × 10^9 N x m2/C2) A) 48 kV B) 48 V C) 96 V D) 96 kV E) 0 V
D) 4.7 m from the 0 cm mark
A +5.00-uC point charge is placed at the 0.0 cm mark of a meter stick and a -4.00-uC point charge is placed at the 50.0 cm mark. At what point on a line through the ends of the meter stick is the electric field equal to zero? A) 2.9 m from the 0 cm mark B) 3.3 m from the 0 cm mark C) 1.4 m from the 0 cm mark D) 4.7 m from the 0 cm mark E) 2.5 m from the 0 cm mark
A) 4.7 m from the 0 cm mark
A +5.00-uC point charge is placed at the 0.0 cm mark of a meter stick and a -4.00-uC point charge is placed at the 50.0 cm mark. At what point on a line through the ends of the meter stick is the electric field equal to zero? A) 4.7 m from the 0 cm mark B) 2.9 m from the 0 cm mark C) 3.3 m from the 0 cm mark D) 2.5 m from the 0 cm mark E) 1.4 m from the 0 cm mark
A) the aluminum
A 10-kg piece of aluminum sits at the bottom of a lake, right next to a 10-kg piece of lead, which is much denser than aluminum. Which one has the greater buoyant force on it? A) the aluminum B) Both have the same buoyant force. C) the lead D) It cannot be determined without knowing their volumes.
A) 1.96 kN
A 12,000-N car is raised using a hydraulic lift, which consists of a U-tube with arms of unequal areas, filled with oil with a density of 800 kg/m3 and capped at both ends with tight-fitting pistons. The wider arm of the U-tube has a radius of 18.0 cm and the narrower arm has a radius of 5.00 cm. The car rests on the piston on the wider arm of the U-tube. The pistons are initially at the same level. What is the force that must be applied to the smaller piston in order to lift the car after it has been raised 1.20 m? For purposes of this problem, neglect the weight of the pistons. A) 1.96 kN B) 1.20 kN C) 0.954 kN D) 3.67 kN E) 1.88 kN
E) 0.27 A
A 120-V rms voltage is applied across a 6.0-uF capacitor. If the frequency of the generator is 60 Hz, what is the rms value of the current in the circuit? A) 0.37 A B) 0.071 A C) 0.47 A D) 0.17 A E) 0.27 A
A) 2.8 N
One point charge + Q is placed at the center of a square, and a second point charge - Q is placed at the upper-left corner of the square. It is observed that an electrostatic force of magnitude 2.0 N acts on the positive charge at the center. Now a third charge - Q is placed at the lower-left corner of the square, as shown in the figure. What is the magnitude of the net force that acts on the center charge now? A) 2.8 N B) 0.0 N C) 4.0 N D) 5.3 N
D) a virtual image, 1.3 cm tall, 20.0 cm same side as the object
A 4.0-cm-tall object is placed 60.0 cm from a diverging lens having a focal length of magnitude 30.0 cm. What is the nature and location of the image? A) a virtual image, 4.0 cm tall, 20 cm other side of the object B) a virtual image, 2.0 cm tall, 10 cm other side of the object C) a real image, 4.0 cm tall, 20 cm other side of the object D) a virtual image, 1.3 cm tall, 20.0 cm same side as the object E) a real image, 1.3 cm tall, 20.0 cm same side as the object
A) 6.0 V
A 4.0-ohm resistor is connected to a 12-ohm resistor and this combination is connected to an ideal dc power supply with voltage V as shown in the figure. If the total current in this circuit is I = 2.0 A, what is the value of voltage V ? A) 6.0 V B) 8.0 V C) 3.0 V D) 1.5 V E) 2.0 V
E) 440 ohm
A 6.0 - uF capacitor is connected to an ac signal with a frequency of 60 Hz. If the maximum voltage applied to the capacitor is 8.0 V, what is its capacitive reactance? A) 6.0 ohm B) 160 ohm C) 7.5 × 10^-6 ohm D) 740 ohm E) 440 ohm
D) 31 % of the maximum charge
A 6.0 - uF uncharged capacitor is connected in series with a 4.0 -kohm resistor , an ideal 20-V dc source, and an open switch. If the switch is closed at time t = 0.0 s, what is the charge on the capacitor at t = 9.0 ms? A) 0 C B) 68% of the minimum charge C) 96% of the maximum charge D) 31 % of the maximum charge E) 37% of the minimum charge
D) 2.2 mrad
A camera used for aerial mapping has a lens with a 30-cm diameter maximum aperture and a 42-cm focal length. Light of 550 nm wavelength is used to form the image. Assuming that the resolution of the camera is limited only by diffraction, what is the smallest angle (in milliradians) subtended by an object on the ground that can be resolved by this camera at maximum aperture? A) 4.5 mrad B) 6.3 mrad C) 1.6 mrad D) 2.2 mrad E) 3.2 mrad
A) 75 V
A capacitor has a voltage of 405 V applied across its plates, and then the voltage source is removed. What is the potential difference across its plates if the space between them is then filled with mica, having a dielectric constant of 5.4? A) 75 V B) 664 V C) 2186 V D) 19,343 V
C) 40 cm
A cell phone is placed 40 cm in front of a converging lens with a focal length of magnitude 20 cm. How far is the image of this phone from the lens? A) 20 cm B) 13 cm C) 40 cm D) 10 cm E) 60 cm
C) 2R .
A charged particle is observed traveling in a circular path of radius R in a uniform magnetic field. If the particle were traveling twice as fast, the radius of the circular path would be A) 8R . B) 4R . C) 2R . D) R/4. E) R/2
A) The image always remains virtual. C) The image keeps getting larger and larger. D) The image gets closer and closer to the lens.
Starting from very far away, an object is moved closer and closer to a diverging lens, eventually reaching the lens. What happens to its image formed by that lens? (There could be more than one correct choice.) A) The image always remains virtual. B) The image eventually changes from real to virtual. C) The image keeps getting larger and larger. D) The image gets closer and closer to the lens. E) The image gets farther and farther from the lens
E) 227 kN
The bathyscaphe Trieste consists of a thin-walled but very strong cylindrical hull, 15.2 m long and 3.66 m in diameter, filled with gasoline with a density of 880 kg/m 3 to make it buoyant. If it is totally submerged in seawater with a density of 1025 kg/m 3 and neither rising nor sinking, what is the weight of the Trieste craft? A) 327 kN B) 427 kN C) 127 kN D) 527 kN E) 227 kN
A) The pressure everywhere in the oil will increase by change p . D) The increase in the force on the top of the chamber will be the same as the increase in the force on the bottom of the chamber.
A closed cubical chamber resting on the floor contains oil and a piston. If you push down on the piston hard enough to increase the pressure just below the piston by an amount change p , which of the following statements is correct? (There could be more than one correct choice.) A) The pressure everywhere in the oil will increase by change p . B) The pressure at the top of the oil will increase by less than change p C) The pressure at the bottom of the oil will increase by more than change p D) The increase in the force on the top of the chamber will be the same as the increase in the force on the bottom of the chamber. E) The pressure on the sides of the chamber will not increase
D) 4E
A coil of wire containing N turns is in an external magnetic field that is perpendicular to the plane of the coil and it steadily changing. Under these circumstances, an emf E is induced in the coil. If the rate of change of the magnetic field and the number of turns in the coil are now doubled (but nothing else changes), what will be the induced emf in the coil? A) 2E B) E/4 C) E/2 D) 4E E) E
C) 12 V
A coil with a self-inductance of 6.0 H is connected to a dc battery through a switch. As soon as the switch is closed, the rate of change of current is 2.0 A/s. What is the emf induced in this coil at this instant? A) 6.0 V B) 3.0 V C) 12 V D) 0.33 V E) 0.0 V
E) 0.60 V
A conducting rod of length l = 25 cm is placed on a U-shaped metal wire that is connected to a lightbulb having a resistance of 8.0 ohm , as shown in the figure. The wire and the rod are in the plane of the page. A constant uniform magnetic field of strength 0.40 T is applied perpendicular to and into the paper. An applied external force pulls the rod to the right with a constant speed of 6.0 m/s. What is the magnitude of the emf induced in the rod? A) 0.20 V B) 0.30 V C) 0.50 V D) 0.40 V E) 0.60 V
B) It is 2 times as large.
The length of a certain wire is doubled while its radius is kept constant. What is the new resistance of this wire? A) It is 1/2 as large. B) It is 2 times as large. C) It is 4 times as large. D) It is 3 times as large. E) It stays the same
A) 2 uT
The magnetic field at a distance of 2 cm from a long straight current-carrying wire is 4 uT. What is the magnetic field at a distance of 4 cm from this wire? A) 2 uT B) 6 uT C) 8 uT D) 4 uT E) 10 uT
A) The electric field is zero inside the conductor. C) The electric field just outside the surface of the conductor is perpendicular to the surface. D) All the free electrons go to the surface of the conductor.
A conductor is placed in a steady external electric field. Which of the following statements are correct for this situation? (There could be more than one correct choice.) A) The electric field is zero inside the conductor. B) The surface of the conductor is neutral. C) The electric field just outside the surface of the conductor is perpendicular to the surface. D) All the free electrons go to the surface of the conductor. E) None of the above statements are correct.
B) between f and 2f .
A convex lens has focal length f . If an object is placed at a distance beyond 2f from the lens on the principal axis, the image is located at a distance from the lens A) of 2f . B) between f and 2f . C) of f . D) between the lens and f . E) of infinity
A) upright and reduced.
A convex mirror has a focal length of magnitude f . An object is placed in front of this mirror at a point 2/3 f from the face of the mirror. The image will appear A) upright and reduced. B) inverted and reduced. C) inverted and enlarged. D) upright and enlarged. E) behind the mirror.
D) 56 dB
A crying baby emits sound with an intensity of 8.0 × 10-8 W/m2 . Calculate a reasonable estimate for the intensity level from a set of quintuplets (five babies), all crying simultaneously at the same place? The lowest detectable intensity is 1.0 × 10 -12 W/m 2 . A) 49 dB B) 36 dB C) 69 dB D) 56 dB E) 79 dB
B) 0.52 N x m
A flat circular coil has 200 identical loops of very thin wire. Each loop has an area of 0.12 m2 and carries 0.50 A of current. This coil is placed in a magnetic field of 0.050 T oriented at 30° to the plane of the loop. What is the magnitude of the magnetic torque on the coil? A) 5.2 N x m B) 0.52 N x m C) 2.5 N x m D) 0.25 N x m
D) 6.3 × 10 -3 T x m 2
A flat circular loop of radius 0.10 m is rotating in a uniform magnetic field of 0.20 T. Find the magnetic flux through the loop when the plane of the loop and the magnetic field vector are perpendicular. A) 0 T x m 2 B) 3.1 × 10 -3 T x m 2 C) 5.5 × 10 -3 T x m 2 D) 6.3 × 10 -3 T x m 2
D) 0.68 mm
A lab specimen is 15.2 mm from a converging lens. The image is 4.0 mm tall and 9.0 cm from the lens. How tall is the specimen? A) 6.8 mm B) 5.4 mm C) 1.7 mm D) 0.68 mm
C) at C
A lighted candle is placed a short distance from a plane mirror, as shown in the figure. At which location will the image of the flame appear to be located? A) at A B) at B C) at C D) at M (at the mirror)
E) Its speed is zero
A mass on a spring undergoes SHM. When the mass is at its maximum distance from the equilibrium position, which of the following statements about it are true? (There could be more than one correct choice.) A) Its total mechanical energy is zero. B) Its kinetic energy is a maximum. C) Its acceleration is zero. D) Its elastic potential energy is zero. E) Its speed is zero
C) The wavelength is 4L and there is a displacement antinode at the pipe's open end.
A pipe of length L that is closed at one end and open at the other end is resonating at its fundamental frequency. Which statement about the sound is correct? A) The wavelength is L and there is a displacement antinode at the pipe's open end. B) The wavelength is L and there is a displacement node at the pipe's open end. C) The wavelength is 4L and there is a displacement antinode at the pipe's open end. D) The wavelength is 4L and there is a displacement node at the pipe's open end.
A) It decreases.
The plates of a parallel-plate capacitor are maintained with constant voltage by a battery as they are pulled apart. What happens to the strength of the electric field between the plates during this process? A) It decreases. B) It increases. C) It remains constant. D) It cannot be determined from the information given
A) is repelled by the sphere.
A plastic rod is charged up by rubbing a wool cloth, and brought to an initially neutral metallic sphere that is insulated from ground. It is allowed to touch the sphere for a few seconds, and then is separated from the sphere by a small distance. After the rod is separated, the rod A) is repelled by the sphere. B) is attracted to the sphere. C) feels no force due to the sphere
E) 480 V
The primary coil of an ideal transformer has 100 turns and its secondary coil has 400 turns. If the ac voltage applied to the primary coil is 120 V, what voltage is present in its secondary coil? A) 100 V B) 70 V C) 30 V D) 400 V E) 480 V
C) Their electric potential energy keeps decreasing. D) Their kinetic energy keeps increasing.
A proton and an electron are released from rest, with only the electrostatic force acting. Which of the following statements must be true about them as they move toward each other? (There could be more than one correct choice.) A) Their kinetic energy keeps decreasing. B) Their electric potential energy keeps increasing. C) Their electric potential energy keeps decreasing. D) Their kinetic energy keeps increasing. E) Their acceleration keeps decreasing
D) leads the voltage by 90°.
A pure capacitor is connected to an ac power supply. In this circuit, the current A) lags the voltage by 180°. B) is in phase with the voltage. C) lags the voltage by 90°. D) leads the voltage by 90°. E) None of the given answers are correct
D) lags the voltage by 90°.
A pure inductor is connected to an ac power supply. In this circuit, the current A) lags the voltage by 45°. B) is in phase with the voltage. C) leads the voltage by 45°. D) lags the voltage by 90°. E) leads the voltage by 90°
B) 100 W.
The primary of an ideal transformer has 100 turns and its secondary has 200 turns. Neglecting frictional losses, if the power input to the primary is 100 W, we can expect the power output of the secondary to be A) 200 W. B) 100 W. C) 50 W. D) none of the given answers
A) perpendicular to and into the page
A rectangular coil, with corners labeled ABCD, has length L and width w . It is placed between the poles of a magnet, as shown in the figure If there is a current I flowing through this coil in the direction shown, what is the direction of the force acting on section AB of this coil? A) perpendicular to and into the page B) perpendicular to and out of the page C) in the direction of the magnetic field D) in the opposite direction of the magnetic field E) The force is zero
A) 63% of the maximum current.
A resistor and an inductor are connected in series to a battery. The time constant for the circuit represents the time required for the current to reach A) 63% of the maximum current. B) 25% of the maximum current. C) 100% of the maximum current. D) 37% of the maximum current. E) 75% of the maximum current.
D) zero.
A resistor and an inductor are connected in series to an ideal battery of constant terminal voltage. At the moment contact is made with the battery, the voltage across the resistor is A) greater than the battery's terminal voltage. B) less than the battery's terminal voltage, but not zero. C) equal to the battery's terminal voltage. D) zero. E) equal to the voltage across the inductor
A) It decreases by a factor of 2.
A simple ac circuit is composed of a capacitor connected across the terminals of an ac power source. If the frequency of the source is doubled, what happens to the reactance of the capacitor? A) It decreases by a factor of 2. B) It increases by a factor of sqr rt 2 C) It decreases by a factor of 4. D) It increases by a factor of 2. E) It increases by a factor of 4.
A) 2d.
A small charged plastic ball is vertically above another charged small ball in a frictionless test tube as shown in the figure. The balls are in equilibrium a distance d apart. If the charge on each ball is doubled, the equilibrium distance between the balls in the test tube would become A) 2d. B) 4d. C) 8d. D) d/4. E) sqr rt 2d
B) 100 times as intense as a sound of 20 decibels.
A sound of 40 decibels is A) 10 times as intense as a sound of 20 decibels. B) 100 times as intense as a sound of 20 decibels. C) four times as intense as a sound of 20 decibels. D) 1000 times as intense as a sound of 20 decibels. E) twice as intense as a sound of 20 decibels
A) 261 N/C
A space probe approaches a planet, taking measurements as it goes. If it detects a potential difference of 6000 MV between the altitudes of 253,000 km and 276,000 km above the planet's surface, what is the approximate electric field strength produced by the planet at 264,500 km above the surface? Assume the electric field strength is approximately constant at these altitudes. A) 261 N/C B) 0.261 N/C C) 493 ȝ N/C D) 561 N/C
A) 0.41 N
The three point charges + 4.0 uC, - 5.0 uC, and - 9.0 uC are placed on the x -axis at the points x = 0 cm, x = 40 cm, and x = 120 cm, respectively. What is the x component of the electrostatic force on the - 9.0 uC charge due to the other two charges? (k = 9.0 × 10^9 N x m 2/C2) A) 0.41 N B) 0.55 N C) 0.64 N D) -0.55 N E) - 0.41 N
E) 1.58
A tank holds a layer of oil, of thickness To = 1.35 m , that floats on a layer of syrup of thickness Ts = 0.760 m, as shown in the figure. Both liquids are clear and do not mix together. A light ray, originating at the bottom of the tank at point P, crosses the oil-syrup interface at a point 0.900 m from the axis. The ray continues and arrives at the oil-air interface, 2.00 m to the right of P and at the critical angle. What is the index of refraction of the oil? A) 1.54 B) 1.62 C) 1.56 D) 1.60 E) 1.58
E) 4d
A very long straight current-carrying wire produces a magnetic field of 20 mT at a distance d from the wire. To measure a field of 5 mT due to this wire, you would have to go to a distance from the wire of A) d sqr rt 2 B) 2d. C) 8d. D) 16d. E) 4d
D) 8 Hz
The wavelengths of the sounds produced by two horns are 6.0 m and 7.0 m, respectively. What beat frequency is heard when the horns are sounded on a day when the speed of sound is 340 m/s? A) 6 Hz B) 7 Hz C) 5 Hz D) 8 Hz
B) 2400 V
Three capacitors are arranged as shown in the figure, with a voltage source connected across the combination. C1 has a capacitance of 4.0 pF, C2 has a capacitance of 8.0 pF, and C 3 has a capacitance of 12.0 pF. Find the potential drop across the entire arrangement if the potential drop across C2 is 402.0 V. A) 740 V B) 2400 V C) 1600 V D) 670 V
A) 0.15 us
Alpha particles, each having a charge of +2e and a mass of 6.64 × 10 -27 kg, are accelerated in a uniform 0.80-T magnetic field to a final orbit radius of 0.30 m. The field is perpendicular to the velocity of the particles. How long does it take an alpha particle to make one complete circle in the final orbit? ( e = 1.60 × 10^-19 C) A) 0.15 us B) 0.49 us C) 0.25 us D) 0.33 us E) 0.40 us
C) 2.3 × 10 5 m/s
An alpha particle (a helium nucleus, having charge +2 e and mass 6.64 × 10-27 kg) moves head-on at a fixed gold nucleus (having charge +79e). If the distance of closest approach is 2.0 × 10 -10 m, what was the speed of the alpha particle when it was very far away from the gold? (k = 9.0 × 10^9, e = 1.60 × 10 -19) A) 2.3 × 10 6 m/s B) 4.6 × 10 5 m/s C) 2.3 × 10 5 m/s D) 4.6 × 10 6 m/s
B) towards the north.
An electron, moving west, enters a magnetic field. Because of this field the electron curves upward. We may conclude that the magnetic field must have a component A) towards the west. B) towards the north. C) downward. D) upward. E) towards the south
D) 800 N
An object has a volume of 4.0 m3 and weighs 40,000 N. What will its apparent weight be in water of density 1000 kg/m3 ? A) 39,200 N B) 40,000 N C) 9,800 N D) 800 N
C) 16 cm
An object is placed 15 cm from a spherical concave mirror with a focal length of magnitude 20 cm. If the object is 4.0 cm tall, how tall is the image? A) 1.0 cm B) 2.0 cm C) 16 cm D) 8.0 cm
C) C
Three equal negative point charges - q are placed at three of the corners of a square of side d as shown in the figure. Which one of the arrows shown represents the direction of the net electric field at the center of the square? A) A B) B C) C D) D
C) it is moving from high potential to low potential and gaining electric potential energy.
As an electron moves in the direction the electric field lines A) it is moving from low potential to high potential and gaining electric potential energy. B) it is moving from low potential to high potential and losing electric potential energy. C) it is moving from high potential to low potential and gaining electric potential energy. D) it is moving from high potential to low potential and losing electric potential energy. E) both its electric potential and electric potential energy remain constant.
A) X and Y are at the same potential.
As shown in the figure, a metal bar is in contact with a pair of parallel rails. A steady, uniform, magnetic field B is present directed to the right. The bar is moving upward with velocity of magnitude v. What is the polarity of the induced emf in terminals X and Y? A) X and Y are at the same potential. B) X is positive and Y is negative. C) Y is positive and X is negative
E) The pressure is the same at each of the labeled points
As shown in the figure, fluid fills a container having several sections. At which of the indicated points is the pressure greatest? A) A B) B C) C D) D E) The pressure is the same at each of the labeled points
C) approaches zero.
As the frequency of the ac voltage across an inductor approaches zero, the inductive reactance of that coil A) approaches infinity. B) becomes negative. C) approaches zero. D) approaches one.
C) 0.01°
Assuming a pupil diameter of 3 mm, what is the angular resolution of the human eye for light at the middle of the visible spectrum (550 nm)? A) 2° B) 2 mrad C) 0.01° D) 0.8° E) 0.2°
D) 955 Hz
At what frequency is the reactance of a 20.0-mH inductor equal to 120 ohm? A) 796 Hz B) 318 Hz C) 1110 Hz D) 955 Hz E) 637 Hz
E) q1 is negative and q2 is positive; the magnitude of q1 is less than the magnitude of q2
Two stationary point charges q1 and q2 are shown in the figure along with a sketch of some field lines representing the electric field produced by them. What can you deduce from the sketch? A) q1 is positive and q2 is negative; the magnitude of q1 is greater than the magnitude of q2 . B) q1 is negative and q2 is positive; the magnitudes are equal. C) q1 and q2 have the same sign; the magnitudes are equal. D) q1 and q2 have the same sign; the magnitude of q1 is greater than the magnitude of q2 . E) q1 is negative and q2 is positive; the magnitude of q1 is less than the magnitude of q2
D) 392 ohm
What is the equivalent resistance of the circuit shown in the figure? The battery is ideal and all resistances are accurate to 3 significant figures. A) 950 ohm B) 450 ohm C) 257 ohm D) 392 ohm
E) a 180° phase change in the reflected beam
When a beam of light that is traveling in air is reflected by a glass surface, there is A) a 60° phase change in the reflected beam. B) a 90° phase change in the reflected beam. C) a 45° phase change in the reflected beam. D) no phase change in the reflected beam. E) a 180° phase change in the reflected beam
C) 4p
When a box rests on a round sheet of wood on the ground, it exerts an average pressure p on the wood. If the wood is replaced by a sheet that has half the diameter of the original piece, what is the new average pressure? A) p/2 B) p/4 C) 4p D) p sqr rt 2 E) 2p
E) its velocity and wavelength change, but its frequency does not change.
When light travels from air into water, A) its velocity, wavelength and frequency all change. B) its frequency changes, but its velocity and wavelength do not change. C) its velocity changes, but its frequency and wavelength do not change. D) its wavelength changes, but its velocity and frequency do not change. E) its velocity and wavelength change, but its frequency does not change.
A) increases by a factor of 16.
When the current through a resistor is increased by a factor of 4, the power dissipated by the resistor A) increases by a factor of 16. B) decreases by a factor of 16. C) increases by a factor of 4. D) increases by a factor of 2. E) decreases by a factor of 4
B) one-fourth its original value.
You double your distance from a sound source that is radiating equally in all directions. What happens to the intensity of the sound? It reduces to A) one-half its original value. B) one-fourth its original value. C) one-sixteenth its original value. D) none of the above
