Physics 3
Two in-phase loudspeakers are 3.00 m apart. They emit sound with a frequency of 490 Hz. A microphone is placed half-way between the speakers and then moved along the line joining the two speakers until the first point of constructive interference is found. At what distance from that midpoint is that first point? The speed of sound in air is 343 m/s. A)0.350 m B)0.500 m C)0.700 m D)0.175 m E)There is no point in that line where constructive interference occurs.
A
A 117 g lead ball is dropped from rest from a height of 7.62 m. The collision between the ball and the ground is totally inelastic. Assuming the ball's kinetic energy goes into heating the ball, find its change in temperature. The specific heat of lead is 128 J/(kg・K) A)1.17 °C B)0.584°C C)0.292°C D)0.146°C E)2.34°C
B
A steel bridge is 1000 m long at -20°C in winter. What is the change in length when the temperature rises to 40°C in summer? The average coefficient of linear expansion of this steel is 11×10^-6 K^-1. A)0.33 m B)0.66 m C)0.55 m D)0.44 m E)0.22 m
B
In a vertical resonating pipe that is open at both ends, there A) are displacement nodes at each end. B) are displacement antinodes at each end. C) is a displacement node at the top end and a displacement antinode at the bottom end. D) is a displacement antinode at the top end and a displacement node at the bottom end. E) No nodes or antinodes can form in vertical pipes.
B
The captain of a spaceship orbiting planet X discovers that to remain in orbit at 410 km from the planet's center, she needs to maintain a speed of 68 m/s. What is the mass of planet X? A)2.8×10^6 kg B)2.8×101^9 kg C)4.2×10^17 kg D)4.2×10^14 kg E)6.7×10^18 kg
B
The intensity level is 65 dB at a distance 5.00 m from a barking dog. What would be a reasonable estimate for the intensity level if two identical dogs very close to each other were barking? You can ignore any interference effects. A)65 dB B)68 dB C)130 dB D)136 dB E)325 dB
B
A cubical box 25.0 cm on each side is immersed in a fluid. The pressure at the top surface of the box is 109.40 kPa and the pressure on the bottom surface is 112.00 kPa. What is the density of the fluid? A)1000 kg/m^3 B)1030 kg/m^3 C)1060 kg/m^3 D)1090 kg/m^3 E)1120 kg/m^3
C
The frequency of the standing wave in a pipe (both ends open) shown in the right figure is 302 Hz. What is the fundamental frequency of the pipe? A)50.5 Hz B)101 Hz C)151 Hz D)252 Hz E)303 Hz
C
Two metal rods are to be used to conduct heat from a region at 100°C to a region at 0°C as shown in the figure. The rods can be placed in parallel, as shown on the left, or in series, as on the right. When steady state flow is established, the heat conducted in the series arrangement is A) greater than the heat conducted with the rods in parallel. B) the same as the heat conducted with the rods in parallel. C) less than the heat conducted with the rods in parallel.
C
You drop a stone down a well that is 9.5 m deep. How long is it before you hear the splash? The speed of sound in air is 343 m/s and air resistance is negligible. A)1.2s B)1.3s C)1.4s D)1.5s E)1.6s
C
74-kg person drinks a thick milkshake of 152,500 cal. How many stairs must this person climb to work off the shake? The height of the stair is 20.0 cm. (1 cal = 4.186 J). A)1760stairs B)421stairs C)352stairs D)4400stairs E)8800stairs
D
A 4.0-kg cylinder of solid iron is supported by a string while submerged in water. What is the tension in the string? The density of iron is 7860 kg/m^3 and that of water is 1000 kg/m^3. A)2.5 N B)20 N C)24 N D)34 N E)40 N
D
In a section of horizontal pipe with a diameter of 4.00 cm the pressure is 95 kPa and water is flowing with a speed of 1.25 m/s. The pipe narrows to 2.00 cm and speeds up to 4.25 m/s. What is the pressure in the narrower region? (Density of water is 1000 kg/m^3) A)95.0 kPa B)43.7 kPa C)116.7 kPa D)86.7 kPa E)77.7 kPa
D
Hearing the siren of an approaching fire truck, you pull over to side of the road and stop. As the truck approaches, you hear a tone of 460 Hz; as the truck recedes, you hear a tone of 410 Hz. How much time will it take to jet from your position to the fire 5.00 km away, assuming it maintains a constant speed? The speed of sound in air is 343 m/s. A)63.5s B)127s C)508s D)52.5s E)254s
E
How much heat must be removed from 456 g of water at 25.0°C to change it into ice at -10.0°C? The specific heat of ice is 2090 J/kg ∙ K, the latent heat of fusion of water is 33.5 × 104 J/kg, and the specific heat of water is 4186 J/kg ∙ K. A)105 kJ B)153 kJ C)57.3 kJ D)47.7 kJ E)210 kJ
E
Object 1 has three times the specific heat capacity and four times the mass of Object 2. The two objects are heated from the same initial temperature, T0, to the same final temperature Tf. During this process, if Object 1 absorbs heat Q, the amount of heat absorbed by Object 2 will be A)12Q. B)6Q. C)3/4 Q. D)4/3Q. E)1/12 Q.
E
Grandfather clocks are designed in a way that the weight at the bottom of the pendulum can be moved up or down by turning a small screw. Suppose you have a grandfather clock at home that runs slow. Should you turn the adjusting screw so as to raise the weight or lower the weight? A) Raise it. B) Lower it. C) It doesn't matter if you raise or lower the weight as long as you displace it by the right amount. D) It doesn't matter if you raise or lower the weight, as long as you displace it with the correct initial velocity. E) Raising or lowering the weight doesn't help. The screw is there so that you can add or take away weight.
A
A 24.5-kg child is standing on the outer edge of a horizontal merry-go-round that has a moment of inertia of 989 kg m^2 about a vertical axis through its center and a radius of 2.40 m. The entire system (including the child) is initially rotating with an angular velocity of 0.180 rad/s. Find the angular velocity if the child moves to a new position 1.10 m from the center of the merry-go-round. A)0.20rad/s B)0.86rad/s C)3.1rad/s D)8.2rad/s E)11rad/s
A
A brother and sister try to communicate with a string tied between two tin cans as shown above. If the string is 9.5 m long, has a mass of 0.032 kg, and pulled taut with a tension of 8.6 N, how much time does it take for a travel from one end of the string to the other? A.0.19s B.0.58s C.12s D.3.6s E. 0.01s
A
A certain glass window reduces the intensity level of the sound from 72 dB to 47 dB. By what factor is the intensity reduced by this glass window? A)3.2×10^-3 B)2.2×10^-2 C)5.6×10^-2 D)1.0×10^-1 E)1.5×10^-1
A
A container consists of two vertical cylindrical columns of different diameter connected by a horizontal section. The open faces of the two columns are closed by very light plates that can move up and down without friction. The tube diameter at A is 35.0 cm and at B it is 10.2 cm. This container is filled with oil of density 0.820 g/cm^3. If a 125-kg object is placed on the larger plate at A, how much mass should be placed on the smaller plate at B to balance it? A) 10.6 kg B) 1470 kg C) 125 kg D) 64.9 kg E) 342 kg
A
A merry-go-round spins freely when Diego moves quickly to the center along a radius of the merry-go-round. As he does this, A) the moment of inertia of the system decreases and the angular speed increases. B) the moment of inertia of the system decreases and the angular speed decreases. C) the moment of inertia of the system decreases and the angular speed remains the same. D) the moment of inertia of the system increases and the angular speed increases. E) the moment of inertia of the system increases and the angular speed decreases.
A
A pipe of length L, that is open at both ends, is resonating at its fundamental frequency. Which statement is correct? A) The wavelength is 2L and there is a displacement node at the pipeʹs midpoint. B) The wavelength is L and there is a displacement antinode at the pipeʹs midpoint. C) The wavelength is L and there is a displacement node at the pipeʹs midpoint. D) The wavelength is 2L and there is a displacement antinode at the pipeʹs midpoint. E) The wavelength is 3L/2 and there are two displacement antinodes located inside the pipe.
A
A puck moves on a horizontal air table. It is attached to a string that passes through a hole in the center of the table. As the puck rotates about the hole, the string is pulled downward very slowly and shortens the radius of rotation, so the puck gradually spirals in towards the center. By what factor will the puck's tangential speed have changed when the string's length has decreased to one-half of its original length? A)2 B)4 C)sqrt(2) D)1 E)1⁄2
A
A solid concrete wall 4.0 m by 2.4 m and 30 cm thick, with a thermal conductivity of 1.3 W/(m ·Co), separates a basement at 18°C from the ground outside at 6°C. How much heat flows through the wall in one hour? A)1.8 MJ B)1.8 kJ C)5.0 kJ D)5.0 MJ E)500 J
A
A whistle produces a sound of frequency of 1.00 kHz. If a listener moves with a speed of 30 m/s away from the whistle, what frequency does this person hear if the sound speed is 340 m/s? A) 912 Hz B) 919 Hz C) 1000 Hz D) 1088 Hz E) 1097 Hz
A
A wood block floats in water with 3⁄4 of its volume above the surface of the water. What is the ratio of the density of the wood block to that of water? A)1/4 B)1/3 C)4/3 D)3/4 E)1/2
A
Consider two simple pendulums, A and B. Pendulum B is nine times as long as pendulum A. Pendulum B is also four times as heavy as pendulum A. The period of pendulum A is T_A. What is the period of pendulum B? A)3 T_A B)9 T_A C)3/2 T_A D)1/2 T_A E)9/4 T_A
A
If you dribble a basketball with a frequency of 1.77 Hz, how long does it take for you to complete 12 dribbles? A.6.78s B.21.2s C.0.32s D.42.5s E.1.07s
A
Suppose NASA wants a satellite to revolve around Earth 5 times a day. What should be the radius of its orbit if we neglect the presence of the Moon? A)1.44×10^7 m B)0.69×10^7 m C)7.22×10^7 m D)2.11×10^7 m E)3.45×10^7 m
A
The period of a simple pendulum that is 1.00 m long on another planet is What is the acceleration due to gravity on this planet if the mass of the pendulum bob is 1.5 kg? A)14.3m/s^2 B)13.3m/s^2 C)15.7m/s^2 D)17.2m/s^2 E)12.5m/s^2
A
The process whereby heat flows by the mass movement of molecules from one place to another is referred to as A) convection. B) evaporation. C) radiation. D) conduction. E) inversion.
A
Two strings both vibrate at exactly 819 Hz. The tension in one of them is then increased slightly. As a result, six beats per second are heard when both strings vibrate. What is the new frequency of the string that was tightened? A)825 Hz B)813 Hz C)822 Hz D)816 Hz E)798 Hz
A
Water flowing through a cylindrical pipe suddenly comes to a section of pipe where the diameter decreases to 86% of its previous value. If the speed of the water in the larger section of the pipe was 32 m/s what is its speed in this smaller section if the water behaves like an ideal incompressible fluid? A) 43 m/s B) 37 m/s C) 28 m/s D) 24 m/s
A
Water flows through a 0.25-cm radius pipe connected to a 0.5-cm radius pipe. Compared to the speed of the water v in the 0.25-cm radius pipe, the speed in the 0.5-cm radius pipe is: A)1/4 v B)1/2 v C)v D)2 v E)4 v
A
When a 0.35-kg package is attached to a vertical spring and lowered slowly, the spring stretches 12 cm. The package is now displaced from its equilibrium position and undergoes simple harmonic oscillations when released. What is the period of the oscillations? A)0.70s B)0.48s C)0.29s D)0.077s E)1.4s
A
A runner generates power 753 W (=J/s) of thermal energy. If this heat has to be removed by evaporation, how much water does this runner lose in 25 minutes of running? The latent heat of vaporization of water is 22.6 × 10^5 J/kg. A)125 g B)500 g C)830 g D)380 g E)980 g
B
A satellite completes one full orbit around Earth. The work performed by Earthʹs gravitational force on the satellite is A) positive most of the time. B) zero C) negative most of the time. D) always positive. E) always negative.
B
A sewing machine needle moves with a frequency of 2.5 Hz. Approximately how long does it take it to move from the highest point to the lowest point in its travel? A) 0.80 s B) 0.20 s C) 1.25 s D) 0.40 s E) 0.10 s
B
A simple harmonic oscillator is undergoing oscillations with an amplitude A. How far is it from its equilibrium position when the kinetic and potential energies are equal? A)A/3 B)A/2 C)A/2 D)A E)A/3
B
A tsunami, an ocean wave generated by an earthquake, propagates along the open ocean at 700 km/hr and has a wavelength of 750 km. What is the frequency of the waves in such a tsunami? A)0.933Hz B)0.000259Hz C)1.07Hz D)6.76 Hz E)0.148 Hz
B
A 5.0-g lead bullet is fired into a fence post. The initial speed of the bullet is 250 m/s, and when it comes to rest, half its kinetic energy goes into heating the bullet. How much does the bullet temperature increase? The specific heat of lead is 128 J/(kg・K). A)60 K B)122 K C)180 K D)30 K E)240 K
B
A 65-kg person sits on a four-leg chair whose mass is 5.0 kg. Each leg of the chair makes contact with the floor in a circle that is 0.020 m in diameter. Find pressure exerted on the floor by each leg of the chair, assuming the weight is evenly distributed. (use g = 9.81 m/s2) A)1.4×10^5Pa B)5.5×10^5Pa C)21×10^5Pa D)42×10^5Pa E)10×10^5 Pa
B
A guitar player produces the standing wave pattern on a guitar string shown on the right. The mass of string is m=0.02 kg, the length of the string is L = 60 cm and its tension F=650 N. What is the fundamental frequency of the sound? A.94Hz B.116Hz C.136Hz D.194Hz E.226Hz
B
A guitar player produces the standing wave pattern on a guitar string shown on the right. The mass of string is m=0.02 kg, the length of the string is L = 60 cm and its tension F=650 N. What is the fundamental frequency of the sound? A.94 Hz B.116 Hz C.136 Hz D.194 Hz E.226 Hz
B
A heat transfer of 9.5×10^5 J is required to convert a block of ice at -15.0 °C to water at 15 °C. What was the mass of the block of ice? The specific heat of ice is 2090 J/(kg K), the specific heat of water is 4186 J/(kg K), and the latent heat of fusion of water is 33.5 × 10^4 J/kg. A)1.1 kg. B)2.2 kg C)3.3 kg D)4.4 kg E)5.5 kg
B
A mass is attached to a spring and oscillates with a period T. If the mass is doubled, what is the new period?A)T/2 B)2T C)2T D)T E)T/2
B
A mass of 0.150 kg is attached to a spring with a force constant of 3.58 N/m and undergoes simple harmonic oscillations with an amplitude of 7.50 cm. What is the total mechanical energy of the system? A)0.0201 J B)0.0101 J C)0.269 J D)0.134 J E)0 J
B
A motorcycle and a police car are moving toward one another. The police car emits sound with a frequency of 502 Hz and has a speed of 13.0 m/s. The motorcycle has a speed of 27.0 m/s. What frequency does the motorcyclist hear? The speed of sound in air is 343 m/s. A)521Hz B)563 Hz C)566 Hz D)588 Hz E)599 Hz
B
A quiet radio has an intensity level of about 30 dB. Busy street traffic has a level of about 60 dB. How much greater is the intensity of the street traffic compared to the radio? A) about 10,000 times B) about 1000 times C) about 100 times D) about 10 times E) about the same
B
Suppose you pour water into a container until it reaches a depth of 12 cm. Next, you carefully pour in a 7.2 cm thickness of olive oil so that it floats on the top of water. What is the pressure at the bottom of the container? The densities of oil and water are 920 kg/m^3 and 1000 kg/m^3, respectively. The atmospheric pressure is Patm = 1.013×10^5 Pa. A)1.003×10^5 Pa B)1.03×10^5 Pa C)1.04×10^5Pa D)1.07×10^5 Pa E)1.08×105 Pa
B
The frequency of the standing wave in a pipe (both ends open) shown in the right figure is 202 Hz. What is the fundamental frequency of the pipe? A)50.5Hz B)101Hz C)151Hz D)252Hz E)303Hz
B
The intensity level of a power mower at a distance of 1.0 m is 100 dB. You wake up one morning to find that four of your neighbors are mowing their lawn 20 m from your open bedroom window. What is the intensity level in your bedroom? A)40dB B)80dB C)50dB D)104dB E)400dB
B
The intensity of the waves from a point source at a distance d from the source is I. At what distance from the sources is the intensity equal to 2I ? A)d/2 B)d/sqrt(2) C)d/4 D)d/8 E)d
B
The reason an astronaut on the International Space Station feels weightless is that A) the astronaut is beyond the range of the earth's gravity. B) the astronaut is falling. C) the astronaut is at a point in space where the effects of the moon's gravity and the earth's gravity cancel. D) this is a psychological effect associated with rapid motion. E) the astronaut's acceleration is zero.
B
Two hoops, hoop A and hoop B, roll down a high incline. Hoop A has radius R and mass M and hoop B has radius 2R and mass 8M. They start together from rest at the top of the incline. Hoop A reaches speed v at the bottom of the incline. The speed of hoop B at the bottom of the incline is A)2 v B)v C)√2 v D)0.5 v E)√3v
B
Two in-phase loudspeakers are 3.0 m apart. They emit sound with a frequency of 490 Hz. A microphone is placed half-way between the speakers and then moved along the line joining the two speakers until the next point of constructive interference is found. At what distance from that midpoint is that first point? The speed of sound in air is 343 m/s. A)0.18 m B)0.35 m C)0.50 m D)0.65 m E)There is no point in that line where constructive interference occurs.
B
Two in-phase loudspeakers are 3.00 m apart. They emit sound with a frequency of 490 Hz. A microphone is placed half-way between the speakers and then moved along the line joining the two speakers until the first point of constructive interference is found. At what distance from that midpoint is that first point? The speed of sound in air is 343 m/s. A) 0.175 m B) 0.350 m C) 0.500 m D) 0.700 m E) There is no point in that line where constructive interference occurs.
B
What is the length of a simple pendulum with a period of 2.0s? A)20 m B)0.99 m C)1.2 m D)1.6 m E)0.87 m
B
A 0.250-kg stone is attached to an ideal spring and undergoes simple harmonic oscillations with a period of 0.640 s. What is the force constant (spring constant) of the spring? A)2.45N/m B)12.1N/m C)24.1N/m D)0.102N/m E)0.610N/m
C
A 0.46-kg mass attached to a spring undergoes a simple harmonic motion with a period of 0.77 s. What is the force constant of the spring? A.8.2N/m B.3.6N/m C.31N/m D.62N/m E.0.78N/m
C
A 15.0-m rope is pulled taut with a tension of 140 N. Waves propagate along the rope with a speed of 27.5 m/s. What is the mass of the rope? A)1.67kg B)5.09kg C)2.78kg D)3.19kg E)2.10kg
C
A column of water of height 70.0 cm supports a column of an unknown liquid as suggested in the right figure (not drawn to scale). Assume that both liquids are at rest and that the density of water is 1.0×103 kg/m3. Determine the density of the unknown liquid. A) 1.0×10^3 kg/m^3 B) 1.3×10^3 kg/m^3 C) 2.6×10^3 kg/m^3 D) 3.9×10^3 kg/m^3 E) 4.2×10^3 kg/m^3
C
A disk, a hoop, and a solid sphere are released at the same time at the top of an inclined plane. They all have equal masses and radii and roll without slipping. In what order do they reach the bottom? A)disk,hoop,sphere B)hoop,sphere,disk C)sphere,disk,hoop D)sphere,hoop,disk E)hoop,disk,sphere
C
A motorcycle and a police car are moving toward one another. The police car emits sound with a frequency of 502 Hz and has a speed of 27.0 m/s. The motorcycle has a speed of 13.0 m/s. What frequency does the motorcyclist hear? The speed of sound in air is 343 m/s. A)521Hz B)544Hz C)566Hz D)588Hz E)599Hz
C
A person who weighs 550 N empties her lungs as much as possible and is then completely immersed in water while suspended from a harness. Her apparent weight is now 21.2 N. What is her density? A)1030kg/m^3 B)56.1kg/m^3 C)1040kg/m^3 D)1050kg/m^3 E) 960 kg/m3
C
A piano wire of linear mass density 0.0050 kg/m is under a tension of 1350 N. What is the wave speed in this wire? A)130 m/s B)260 m/s C)520 m/s D)1040 m/s E)2080 m/s
C
A piece of metal rests in a toy wood boat floating in water in a bathtub. If the metal is removed from the boat, and kept out of the water, what happens to the water level in the tub? A) It does not change. B) It goes up. C) It goes down. D) It is impossible to determine without knowing the density of the metal. E) It is impossible to determine without knowing the weight of the metal.
C
A pipe contains water flowing with a speed of 1.6 m/s. When the pipe narrows to one-half its original diameter, what is the speed of the water? A) 1.6 m/s B) 3.2 m/s C) 6.4 m/s D) 9.6 m/s E) 12.8 m/s
C
A quiet radio has an intensity level of about 20 dB. Busy street traffic has a level of about 40 dB. How much greater is the intensity of the street traffic compared to the radio? A) about 10,000 times B) about 1000 times C) about 100 times D) about 10 times E) about the same
C
A runner generates power 1250 W (=J/s) of thermal energy. If this heat has to be removed by evaporation, how much water does this runner lose in 25 minutes of running? The latent heat of vaporization of water is 22.6 × 105 J/kg. A)125g B)500g C)830g D)380g E)980g
C
A wave traveling along a stretched horizontal rope. The vertical distance from crest to trough for this wave is 26 cm and the horizontal distance from crest to trough is 28 cm. What are the wavelength and amplitude of the wave. Choose a correct set of (wavelength, amplitude). A.(28 cm, 13 cm) B.(56 cm, 26 cm) C.(56 cm, 13 cm) D.(14 cm, 13 cm) E. (14 cm, 26 cm)
C
In many cartoon shows, a character runs of a cliff, realizes his predicament and lets out a scream. He continues to scream as he falls. If the physical situation is portrayed correctly, from the vantage point of an observer at the foot of the cliff, the pitch of the scream should be A) lower than the original pitch and constant. B) lower than the original pitch and decreasing as he falls. C) higher than the original pitch and increasing as he falls. D) higher than the original pitch and constant. E) It is impossible to predict.
C
Neptune orbits the Sun at a distance of 2.795 billion miles. The gravitational force by the Sun on Neptune is F. The force by Neptune on the Sun is ... A) smaller than F, because Neptune is so far away from the Sun. B) smaller than F, because Neptune is much lighter than the Sun. C) equal to F. D) larger than F, because Neptune is moving around the Sun. E) larger than F, because of the presence of the other planets.
C
Two timpani (tunable drums) are played at the same time. One is correctly tuned so that when it is struck, sound is produced that has a wavelength of 2.24 m. The second produces sound with a wavelength of 2.08 m. If the speed of sound is 343 m/s, what beat frequency is heard? A)8.05Hz B)10.2Hz C)11.8Hz D)14.5Hz E)16.8Hz
C
Water flows out of a large reservoir with a diameter of 16.4 m through a narrow pipe 8.0 m below the surface, as shown in the figure. What is the speed of the water as it comes out of the pipe? A)8.9 m/s B)9.9 m/s C)13 m/s D)14 m/s E)16 m/s
C
What is the frequency of a pressure wave of wavelength 2.5 m that is traveling at 1400 m/s? A)178 Hz B)1.78 kHz C)560 Hz D)5.6 kHz E)17.8 MHz
C
A fisherman fishing from a pier observes that the float on his line bobs up and down, taking 2.4 s to move from its highest point to its lowest point. He also estimates that the distance between adjacent wave crests is 48 m. What is the speed of the waves going past the pier? A)20 m/s B)4.8 m/s C)1.0 m/s D)10 m/s E)120 m/s
D
A heat transfer of 19×10^5 J is required to convert a block of ice at -15.0 °C to water at 15 °C. What was the mass of the block of ice? The specific heat of ice is 2090 J/(kg K), the specific heat of water is 4186 J/(kg K), and the latent heat of fusion of water is 33.5 × 10^4 J/kg. A)1.1 kg. B)2.2 kg C)3.3 kg D)4.4 kg E)5.5 kg
D
A piece of wood with density of 706 kg/m3 is tied with a string to the bottom of a water-filled flask (see the right figure). The wood is completely immersed, and has a volume of 8.00×10-6 m3. What is the tension in the string? The density of water is 1000 kg/m3. (Use g = 9.81 m/s2) A)0.0554N B)0.0785N C)0.133N D)0.0231N E) 0.101 N
D
A planet has two small satellites in circular orbits around the planet. The first satellite has a period 18.0 hours and an orbital radius 2.00 × 10^7 m. The second planet has an orbital radius 3.00 × 10^7 m. What is the period of the second satellite? A) 27.0 hours B) 12.0 hours C) 60.8 hours D) 33.1 hours E) 9.80 hours
D
A pressurized cylindrical tank, 5.0 m in diameter, contains water that emerges from the pipe at point C with a speed of 13 m/s as shown in the figure. Point A is 10 m above point B and point C is 3.0 m above point B. The area of the pipe at point B is 0.080 m2 and the pipe narrows to an area of 0.040 m2 at point C. Assume that the water is an ideal fluid. The density of water is 1000 kg/m3 The mass flow rate in the pipe is closest to A)310 kg/s B)360 kg/s C)420 kg/s D)520 kg/s E)470 kg/s
D
An incompressible fluid flows steadily through a pipe that has a change in diameter. The fluid speed at a location where the pipe diameter is 8.0 cm is 1.28 m/s. What is the fluid speed at a location where the diameter has narrowed to 4.0 cm? A)1.28m/s B)0.32m/s C)0.64m/s D)5.12m/s E)2.56m/s
D
At their closest approach, Venus and Earth are 4.20 × 10^10 m apart. The mass of Venus is4.87×10^24 kg and the mass of Earth is 5.97 × 1024 kg. What is the magnitude of the gravitational force exerted by Venus on Earth at that point? A)6.30×10^20 N B)5.43×10^26 N C)4.62×10^28 N D)1.10×10^18 N E)1.72×10^19 N
D
In a section of horizontal pipe with a diameter of 4.00 cm the pressure is 95 kPa and water is flowing with a speed of 1.25 m/s. The pipe narrows to 2.00 cm and speeds up to 4.25 m/s. What is the pressure in the narrower region? (Density of water is 1000 kg/m3) A)95.0 kPa B)43.7 kPa C)116.7 kPa D)86.7 kPa E)77.7 kPa
D
Physicists often solve problems using ideas that can be applied in other similar situations. Here is an example of what I mean: In a certain one-lane road there are no entrances or exits. As the road passes through open country and populated areas, the speed limit changes. Assume that cars travel at the posted speed limit. In the open road, where the speed limit is 55 mph, the cars are spaced so there are 51 cars per mile (think of this as a linear density). If the flow of cars is steady, how many cars per mile are there in a stretch of road where the speed limit is 40 mph? A)60cars/mile B)76cars/mile C)66cars/mile D)70cars/mile E)56cars/mile
D
The acceleration due to gravity on the surface of Earth is g. Calling R the radius of Earth, at what distance from Earthʹs center would the acceleration due to gravity drop to g/16? A)2R B)16R C)R/16 D)4R E)R/4
D
The right figure shows four containers, each filled with water to the same level. Which one of the followings is correct for pressure of the containers at the depth h. A)A>C>D>B B)A>C>B=D C)A>C=B=D D)A=C=B=D E)A<C<B < D
D
Three containers (the right figure) are filled with water to the same height and have the same surface area at the base, but the total weight of water is different for each. Which container has the greatest pressure acting on its base? A) container 1 B) container 2 C) container 3 D) all three are equal E) cannot determine
D
Transverse waves travel at 43.2 m/s in a string that is subjected to a tension of 60.5 N. If the string is 15.9 m long, what is its mass? A)0.597 kg B)0.216 kg C)0.366 kg D)0.515 kg E)0.714 kg
D
You blow into an open pipe and produce a tone. What happens to the frequency of the tone if you close the end of the pipe and blow into it again? A) depends on the speed of sound in the pipe B) you hear the same frequency C) you hear a higher frequency D) you hear a lower frequency
D
14) When atmospheric pressure increases, what happens to the absolute pressure at the bottom of a pool? A) It increases by a lesser amount. B) It increases by a greater amount. C) It does not change. D) It depends on the depth of the pool. E) It increases by the same amount.
E
A 10 cm long tube has one open end and one closed end. Blowing over the open end produces a sound with the fundamental wavelength of 890 Hz A)2.5 cm B)5.0 cm C)10 cm D)20 cm E)40 cm
E
A 74-kg person drinks a thick milkshake of 305,000 cal. How many stairs must this person climb to work off the shake? The height of the stair is 20.0 cm. (1 cal = 4.186 J). A)1760stairs B)421stairs C)352stairs D)4400stairs E)8800stairs
E
A mass of 0.150 kg is attached to a spring with a force constant of 3.58 N/m and undergoes simple harmonic oscillations. What is the period of the oscillations? A)2.57s B)0.527s C)0.263s D)1.14s E)1.29s
E
A mass on a spring undergoes Simple Harmonic Motion. When the mass passes through the equilibrium position, which of the following statements about it are true? A) Its speed is zero. B) Its acceleration is maximum. C) Its total mechanical energy is zero. D) Its elastic potential energy is maximum. E) Its kinetic energy is a maximum.
E
A pendulum of length L has a period T. How long must the pendulum be if its period is to be 2T. A.L/4 B.L/2 C.L D.2L E.4L
E
A solid uniform cylinder is rolling without slipping. What fraction of its kinetic energy is rotational? A)3/4 B)1/2 C)1/4 D)2/3 E)1/3
E
A sound of 40 decibels is A) 10 times as intense as a sound of 20 decibels B) 1000 times as intense as a sound of 20 decibels C) four times as intense as a sound of 20 decibels D) twice as intense as a sound of 20 decibels E) 100 times as intense as a sound of 20 decibels.
E
A styrofoam sphere of radius R has an initial density ρ0. You now carefully compress the sphere so its radius is R/2. What is the density of the compressed sphere? A)2 ρ_0 B)4 ρ_0 C)ρ_0 sqrt(8) D)ρ_0 sqrt(2) E)8 ρ_0
E
A wire that is 1.0 m long with a mass of 0.090 kg is under a tension of 710 N. When a transverse wave travels on the wire, its wavelength is 0.10 m and its amplitude is 6.5 mm. What is the frequency of this wave? A)1200 Hz B)1000 Hz C)920 Hz D)1500 Hz E)890 Hz
E
A wooden raft has a mass of 55 kg. With no load the raft floats in water (density 1000 kg/m3) with 64% of its volume submerged. What maximum mass of sand can be put on the raft without sinking it? A)45kg B)20kg C)35kg D)86kg E)31kg
E
In order to produce beats, the two sound waves should have A) the same frequency. B) the same amplitude. C) slightly different amplitudes. D) the same period. E) slightly different frequencies.
E
Object 1 has three times the specific heat capacity and four times the mass of Object 2. The two objects are heated from the same initial temperature, T_0, to the same final temperature T_f. You determine that the amount of heat gained by Object 1 is Q. The amount of heat absorbed by Object 2 will be A)12Q. B)6Q. C)3/4Q. D)4/3Q. E)1/12Q
E
Object 1 has two times the specific heat capacity and four times the mass of Object 2. The two objects are heated from the same initial temperature, T0, to the same final temperature Tf. You determine that the amount of heat gained by Object 1 is Q. The amount of heat absorbed by Object 2 will be A)12Q. B)8Q. C)3/4 Q D)1/12Q. E)1/8 Q
E
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 2.16 m on each side? A)4.51×10^5 N B)5.87×10^4 N C)5.46×10^5N D)6.14×10^5 N E)5.19×104 N
E
Refer to the figure above. A bimetallic strip, consisting of metal G on the top and metal H on the bottom, is rigidly attached to a wall at the left. The coefficient of linear thermal expansion for metal G is greater than that of metal H. If the strip is uniformly heated, it will A) curve upward. B) remain horizontal, but get longer. C) remain horizontal, but get shorter. D) bend in the middle. E) curve downward.
E
The deepest point of the Pacific Ocean is 11,033 m, in the Mariana Trench. What is the water pressure at that point? The density of seawater is 1025 kg/m3. A)2.22×10^8Pa B)5.55×10^7Pa C)8.88×10^7Pa D)3.33×10^8Pa E)1.11×10^8Pa
E
The position of a simple harmonic oscillator is given by x(t)=(0.50m)cos(pi/3t) where t is in seconds. What is the period of the oscillator? A)1.0s B)2.0s C)4.0s D)5.0s E)6.0s
E
The position of mass oscillating on a spring is given by the equation x = (12.4 cm) cos[2(pi)(t)/(0.38s )]. What is the first time that the mass is at the position of x = 0 ? A)0 s B)0.072s C)0.19s D)0.048s E)0.095s
E
The world's longest suspension bridge is the Akashikaikyo Bridge in Japan. The bridge is 3910 m long and is constructed of steel. How much longer is the bridge on a warm summer day (30.0 °C) than on a cold winter day (-10.00 °C)? The coefficient of thermal expansion for steel is(infinity sign) = 12× 10-6 (°C)-1. A)0.75 m. B)0.94 m C)1.41 m D)1.65m E)1.87 m
E
The world's longest suspension bridge is the Akashikaikyo Bridge in Japan. The bridge is 3910 m long and is constructed of steel. How much longer is the bridge on a warm summer day (30.0 °C) than on a cold winter day (0.00 °C)? The coefficient of thermal expansion for steel is (infinity sign) = 12×10-6 (°C)-1. A)0.6m. B)0.8m C)1.0m D)1.2m E)1.4m
E
When a 0.213-kg mass is attached to a vertical spring, it causes the spring to stretch a distance d. If the mass is now displaced slightly from equilibrium, it is found to make 102 oscillations in 56.7 s. Find the stretched distance d. (use g = 9.81 m/s2) A.15.3cm B.2.09cm C.40.3cm D.0cm E.7.68cm
E
When a mass of 0.350 kg is attached to a vertical spring and lowered slowly, the spring stretches a distance d. The mass is now displaced from its equilibrium position and oscillates with an angular frequency w = 12.85 rad/s. What is the stretch distance d? A)2.97cm B)2.35cm C)6.28cm D)4.71cm E)5.93cm
E
