Physics HW-all
On a cold winter day, the outside temperature is -5.0 °C while the interior of a well-insulated garage is maintained at 20.0 °C by an electric heater. Assume the walls have a total area of 75 m 2, a thickness of 0.15 m, and a thermal conductivity of 0.042 W/(m · C°). What is the cost to heat the garage for six hours at these temperatures if the cost of electricity is $ 0.11/kWh? Note: 1 kWh = 3.6 × 10 6 J. A.$ 0.18 B.$ 1.09 C.$ 0.44 D.$ 0.35 E.$ 0.61
$ 0.35
A sample of a monatomic ideal gas is originally at 20 °C. What is the final temperature of the gas if the pressure is doubled and volume is reduced to one-fourth its initial value? A.900 °C B.-130 °C C.10 °C D.80 °C E.-260 °C
-130 °C
A ball is fired at an angle of 45°, the angle that yields the maximum range in the absence of air resistance. What is the ratio of the ball's maximum height to its range? A.0.50 B.0.75 C.0.25 D.1.0 E.0.67
0.25
Two cylindrical steel rods A and B have radii of 0.02 m and 0.04 m, respectively. The two steel rods conduct the same amount of heat per unit time for the same temperature differences between their two ends. What is the ratio of the lengths of the rods, L A/ L B? A.2.00 B.4.00 C.1.00 D.0.25 E.0.50
0.25
A GPS tracking device is placed in a police dog to monitor its whereabouts relative to the police station. At time t 1 = 23 min, the dog's displacement from the station is 1.2 km, 33° north of east. At time t 2 = 57 min, the dog's displacement from the station is 2.0 km, 75° north of east. Find the magnitude and direction of the dog's average velocity between these two times. A.0.52 m/s, 88° north of east B.0.80 m/s, 42° west of north C.0.67 m/s, 21° west of north D.1.6 m/s, 42° north of east E.1.4 m/s, 31° west of north
0.67 m/s, 21° west of north
An ideal gas with a fixed number of molecules is maintained at a constant pressure. At 30.0 °C, the volume of the gas is 1.25 m 3. What is the volume of the gas when the temperature is increased to 150.0 °C? A.1.75 m3 B.6.25 m3 C.1.50 m3 D.2.45 m3 E.0.90 m3
1.75 m3
Two forces act on a 4.5-kg block resting on a frictionless surface as shown. What is the magnitude of the horizontal acceleration of the block? A.3.2 m/s2 B.8.9 m/s2 C.0.82 m/s2 D.1.8 m/s2 E.1.2 m/s2
1.8 m/s2
Determine the minimum angle at which a roadbed should be banked so that a car traveling at 20.0 m/s can safely negotiatethe curve if the radius of the curve is 2.00 × 10 2 m. A.78.2° B.19.6° C.0.581° D.11.5° E.0.200°
11.5°
An airplane flying at 115 m/s due east makes a gradual turn following a circular path to fly south. The turn takes 15 seconds to complete.Reference: Ref 5-7What is the radius of the curve that the plane follows in making the turn? A.830 m B.350 m C.280 m D.1100 m E.1600 m
1100 m
A net force of 25 N is applied for 5.7 s to a 12-kg box initially at rest. What is the speed of the box at the end of the 5.7-s interval? A.12 m/s B.30 m/s C.7.5 m/s D.1.8 m/s E.3.0 m/s
12 m/s
An airplane flying at 115 m/s due east makes a gradual turn following a circular path to fly south. The turn takes 15 seconds to complete.Reference: Ref 5-7What is the magnitude of the centripetal acceleration during the turn? A.zero m/s2 B.9.8 m/s2 C.6.9 m/s2 D.12 m/s2 E.8.1 m/s2
12 m/s2
A train travels due south at 60 m/s. It reverses its direction and travels due north at 60 m/s. What is the change in velocity of the train? A.60 m/s, due south B.zero m/s C.60 m/s, due north D.120 m/s, due north E.120 m/s, due south
120 m/s, due north
At what rate is heat lost through a 1.5 m × 3.0 m rectangular glass windowpane that is 0.4 cm thick when the inside temperature is 22 °C and the outside temperature is 6.0 °C? The thermal conductivity for the glass is 0.75 W/(m · C°). A.560 W B.7200 W C.13 500 W D.1800 W E.3600 W
13 500 W
Heat is conducted by two cylindrical rods, one carbon and one aluminum, with identical cross-sectional area and length. The temperature difference between the ends of each rod is the same. Carbon has a thermal conductivity of 1100 J/(s ⋅ m ⋅ C°) and that of aluminum is 240 J/(s ⋅ m ⋅ C°). What percentage of the total energy transferred by the two rods each second is conducted by the silver rod? A.30 % B.46 % C.18 % D.82 % E.64 %
18 %
A silver coin has a mass of 17.75 g. If the atomic mass of silver is 107.868 u, how many silver atoms are in the coin? A.5.724 × 1022 B.1.390 × 1025 C.2.158 × 1023 D.4.812 × 1023 E.3.660 × 1024
3.660 × 1024
A boat that can travel at 4.0 km/h in still water crosses a river with a current of 2.0 km/h. At what angle must the boat be pointed upstream (that is, relative to its actual path) to go straight across the river? A.30° B.63° C.60° D.90° E.27°
30°
A space station is designed in the shape of a large, hollow donut that is uniformly rotating. The outer radius of the station is 350 m. With what period must the station rotate so that a person sitting on the outer wall experiences "artificial gravity," i.e. an acceleration of 9.8 m/s 2? A.110 s B.38 s C.170 s D.230 s E.76 s
38 s
The second hand on a watch has a length of 4.50 mm and makes one revolution in 60.00 s. What is the speed of the end of the second hand as it moves in uniform circular motion? A.4.71 × 10-4 m/s B.2.36 × 10-5 m/s C.5.34 × 10-3 m/s D.9.42 × 10-4 m/s E.2.67 × 10-3 m/s
4.71 × 10-4 m/s
An automobile tire is inflated to a gauge pressure of 32 lb/in 2 at a temperature of -10.0 °C. Under strenuous driving, the tire heats up to 40.0 °C. What is the new gauge pressure if the volume of the tire remains essentially the same? (atmospheric pressure = 14.7 lb/in 2) A.40.9 lb/in2 B.20.6 lb/in2 C.38.0 lb/in2 D.55.6 lb/in2 E.17.5 lb/in2
40.9 lb/in2
A tank contains 135 moles of the monatomic gas argon at a temperature of 15.3 °C. How much energy must be added to the gas to increase its temperature to 45.0 °C? A.2.50 × 103 J B.3.33 × 104 J C.5.00 × 104 J D.7.50 × 106 J E.5.70 × 105 J
5.00 × 104 J
What is the magnitude of the gravitational force acting on a 79.5-kg student due to a 58.0-kg student sitting 2.40 m away in the classroom? A.1.41 × 10-7 N B.7.91 × 10-10 N C.3.14 × 10-9 N D.5.33 × 10-8 N E.6.29 × 10-8 N
5.33 × 10-8 N
How many molecules are in 0.044 kg of carbon dioxide, CO 2? (atomic masses: C = 12 u; O = 16 u) A.6.02 × 1023 B.44 C.3 D.2.20 × 1024 E.3.85 × 1025
6.02 × 1023
Object A has an emissivity of 0.95; and its temperature is 25 °C. At what temperature (in degrees Celsius) does object B, whose emissivity is 0.50, emit radiation at the same rate as object A if both objects have the same surface area? A.93 °C B.40 °C C.29 °C D.61 °C E.77 °C
77 °C
A tennis ball is thrown from ground level with velocity directed 30° above the horizontal. If it takes the ball 0.5 s to reach the top of its trajectory, what is the magnitude of the initial velocity? A.11.3 m/s B.34.4 m/s C.19.6 m/s D.9.8 m/s E.4.9 m/s
9.8 m/s
While on an interplanetary mission, a 58.5-kg astronaut is floating toward the front of her ship at 0.15 m/s, relative to the ship. She wishes to stop moving, relative to the ship. She decides to throw away the 2.50-kg book she's carrying. What should the approximate speed and direction of the book be to achieve her goal? A.3.7 m/s, toward the front of the ship B.0.15 m/s, toward the front of the ship C.3.5 m/s, toward the back of the ship D.0.30 m/s, toward the back of the ship E.1.5 m/s, toward the front of the ship
A.3.7 m/s, toward the front of the ship
Young's modulus of nylon is 3.7 × 10 9 N/m 2. A force of 6.0 × 10 5 N is applied to a 1.5-m length of nylon of cross sectional area 0.25 m 2. By what amount does the nylon stretch? A.3.9 × 10-3 m B.1.6 × 10-2 m C.9.7 × 10-4 m D.3.1 × 10-2 m E.1.2 × 10-5 m
A.3.9 × 10-3 m
A 0.030-kg ice cube at 0 °C is placed in an insulated box that contains a fixed quantity of steam at 100 °C. When thermal equilibrium of this closed system is established, its temperature is found to be 23 °C. Determine the original mass of the steam at 100 °C. A.5.0 g B.2.5 g C.1.7 g D.0.17 g E.4.8 g
A.5.0 g
A 66-N ⋅ m torque acts on a wheel with a moment of inertia 175 kg ⋅ m 2. If the wheel starts from rest, how long will it take the wheel to make one revolution? A.5.8 s B.0.71 s C.6.9 s D.2.4 s E.0.37 s
A.5.8 s
An object weighs 15 N in air and 13 N when submerged in mineral spirits, which has a density of 788 kg/m 3. Determine the density of the object. A.5.9 × 103 kg/m3 B.330 kg/m3 C.1.2 × 103 kg/m3 D.500 kg/m3 E.7.5 × 103 kg/m3
A.5.9 × 103 kg/m3
One of the largest barometers ever built was an oil-filled barometer constructed in Leicester, England in 1991. The oil had a height of 12.2 m. Assuming a pressure of 1.013 × 10 5 Pa, what was the density of the oil used in the barometer? A.847 kg/m3 B.798 kg/m3 C.981 kg/m3 D.1210 kg/m3 E.1150 kg/m3
A.847 kg/m3
A 4.0-kg ball moves in a straight line at 8.0 m/s as shown in the figure. At the instant shown, what is its angular momentum about the point P? A.85 kg ⋅ m2/s B.160 kg ⋅ m2/s C.zero kg ⋅ m2/s D.110 kg ⋅ m2/s E.33 kg ⋅ m2/s
A.85 kg ⋅ m2/s
A pirate's treasure chest lies 20.0 m below the surface of the ocean. What is the magnitude of the force that acts on the rectangular top that is 0.750 m × 0.425 m? A.9.48 × 104 N B.2.39 × 103 N C.980 N D.4.71 × 105 N E.2.00 × 106 N
A.9.48 × 104 N
A 7.30-kg bowling ball strikes a 1.60-kg pin at rest head-on. Before the collision, the velocity of the ball is +6.00 m/s. After the collision, the velocity of the ball is +5.40 m/s. What is the velocity of the pin after the collision? A.+0.6 m/s B.+2.7 m/s C.+3.2 m/s D.+5.4 m/s E.+1.2 m/s
B.+2.7 m/s
A 10-kg box is at rest at the end of an unstretched spring with constant k = 4000 N/m. The mass is struck with a hammer giving it a velocity of 6.0 m/s to the right across a frictionless surface. What is the amplitude of the resulting oscillation of this system? A.0.4 m B.0.3 m C.0.5 m D.0.6 m E.2 m
B.0.3 m
A grindstone, initially at rest, is given a constant angular acceleration so that it makes 20.0 rev in the first 8.00 s. What is its angular acceleration? A.0.313 rad/s2 B C.1.97 rad/s2 D.2.50 rad/s2 E.0.625 rad/s2
B.3.93 rad/s2
A large tank is filled with water to a depth of 15 m. A spout located 10.0 m above the bottom of the tank is then opened as shown in the drawing. With what speed will water emerge from the spout? A.17 m/s B.9.9 m/s C.31 m/s D.3.1 m/s E.14 m/s
B.9.9 m/s
Which one of the following statements concerning the moment of inertia I is false? A.I depends on the orientation of the rotation axis relative to the particles that make up the object. B.I depends on the angular acceleration of the object as it rotates. C.Of the particles that make up an object, the particle with the smallest mass may contribute the greatest amount to I. D.I depends on the location of the rotation axis relative to the particles that make up the object. E.I may be expressed in units of kg ⋅ m2.
B.I depends on the angular acceleration of the object as it rotates.
A stationary bomb explodes in space breaking into a number of small fragments. At the location of the explosion, the net force due to gravity is zero newtons. Which one of the following statements concerning this event is true? A.The mass of any one fragment must be equal to the mass of any other fragment. B.The vector sum of the linear momenta of the fragments must be zero. C.The sum of the kinetic energies of the fragments must be zero D.Kinetic energy is conserved in this process. E.All of the fragments must have equal kinetic energies.
B.The vector sum of the linear momenta of the fragments must be zero.
At a location where the acceleration due to gravity is 9.807 m/s 2, the atmospheric pressure is 9.891 × 10 4 Pa. A barometer at the same location is filled with an unknown liquid. What is the density of the unknown liquid if its height in the barometer is 1.163 m? A.4336 kg/m3 B.210 kg/m3 C.8672 kg/m3 D.9688 kg/m3 E.5317 kg/m3
C.8672 kg/m3
Two balls of equal size are dropped from the same height from the roof of a building. One ball has twice the mass of the other. When the balls reach the ground, how do the kinetic energies of the two balls compare? A.The lighter one has twice as much kinetic energy as the other does. B.The lighter one has the same kinetic energy as the other does. C.The lighter one has one half as much kinetic energy as the other does. D.The lighter one has four times as much kinetic energy as the other does. E.The lighter one has one fourth as much kinetic energy as the other does.
C.The lighter one has one half as much kinetic energy as the other does.
Zirconium tungstate is an unusual material because its volume shrinks with an increase in temperature for the temperature range 0.3 K to 1050 K (where it decomposes). In fact, the volumetric coefficient of thermal expansion is -26.4 × 10 -6/K. Determine the ratio Δ V/ V 0 for the above mentioned temperature range. Express your answer in percent. A.-1.04% B.-5.28% C.-1.90% D.-3.59% E.-2.77%
E.-2.77%
A helicopter ( m = 3250 kg) is cruising at a speed of 56.9 m/s at an altitude of 185 m. What is the total mechanical energy of the helicopter? A.3.91 × 107 J B.6.91 × 107 J C.2.27 × 108 J D.5.26 × 107 J E.1.12 × 108 J
E.1.12 × 108 J
The Earth takes slightly less than one day to complete one rotation about the axis passing through its poles. The actual time is 8.616 × 10 4 s. Given this information, what is the angular speed of the Earth about its axis? A.9.951 × 10-5 rad/s B.6.334 × 10-4 rad/s C.1.990 × 10-7 rad/s D.2.321 × 10-6 rad/s E.7.292 × 10-5 rad/s
E.7.292 × 10-5 rad/s
Given the following information, determine the relative humidity at 15 °C. partial pressure of water at 15 °C = 1230 Pa partial pressure of water at the dew point, 15 °C = 1710 Pa A.47.9 % B.39.0 % C.64.1 % D.50.8 % E.71.9 %
E.71.9 %
The kinetic energy of a car is 8 × 10 6 J as it travels along a horizontal road. How much work is required to stop the car in 10 s? A.8 × 107 J B.zero joules C.8 × 105 J D.8 × 104 J E.8 × 106 J
E.8 × 106 J
The graph shows the velocities of two objects of equal mass as a function of time. Net forces F A, F B, and F C acted on the objects during intervals A, B, and C, respectively. Which one of the following choices is the correct relationship between the magnitudes of the net forces? A.FC > FB > FA B.FA > FB > FC C.FB = FC > FA D.FA > FB = FC E.FA = FB = FC
FA > FB = FC
An astronaut orbits the earth in a space capsule whose height above the earth is equal to the earth's radius. How does the weight of the astronaut in the capsule compare to her weight on the earth? A.Her weight is equal to zero newtons. B.Her weight is approximately equal to one-half of her weight on earth. C.Her weight is approximately equal to one-third of her weight on earth. D.Her weight is approximately equal to one-fourth her weight on earth. E.Her weight is approximately equal to one-sixteenth her weight on earth.
Her weight is approximately equal to one-fourth her weight on earth.
A football is kicked at an angle θ with respect to the horizontal. Which one of the following statements best describes theacceleration of the football during this event if air resistance is neglected? A.The acceleration is zero m/s2 at all times. B.The acceleration is 9.8 m/s2 at all times. C.The acceleration is zero m/s2 when the football has reached the highest point in its trajectory. D.The acceleration starts at 9.8 m/s2 and drops to some constant lower value as the ball approaches the ground. E.The acceleration is positive as the football rises, and it is negative as the football falls.
The acceleration is 9.8 m/s2 at all times.
A rock is whirled on the end of a string in a horizontal circle of radius R with a constant period T. If the radius of the circle is reduced to R/3, while the period remains T, what happens to the centripetal acceleration of the rock? A.The centripetal acceleration increases by a factor of 3. B.The centripetal acceleration remains the same. C.The centripetal acceleration increases by a factor of 9. D.The centripetal acceleration decreases by a factor of 9. E.The centripetal acceleration decreases by a factor of 3.
The centripetal acceleration decreases by a factor of 3.
A rock is thrown straight up from the earth's surface. Which one of the following statements concerning the net force acting on the rock at the top of its path is true? A.The direction of the net force changes from up to down. B.The net force is greater than the weight of the rock. C.The net force is instantaneously equal to zero newtons. D.The net force is less than the weight of the rock, but greater than zero newtons. E.The net force is equal to the weight of the rock.
The net force is equal to the weight of the rock.
A 2.0-N rock slides on a frictionless inclined plane. Which one of the following statements is true concerning the normal force that the plane exerts on the rock? A.It increases as the angle of inclination, θ, is increased. B.The normal force is zero newtons. C.The normal force is less than 2.0 N, but greater than zero newtons. D.The normal force is 2.0 N. E.The normal force is greater than 2.0 N.
The normal force is less than 2.0 N, but greater than zero newtons.
Which object will emit more electromagnetic radiation than it absorbs from its surroundings? A.an ice cube in beaker of water at 50 °C B.a 200 °C copper coin in a beaker of water at 98 °C C.a girl scout sitting close to a campfire D.an ice cube in thermal equilibrium with the interior of a freezer E.a 600 °C copper sphere in a 700 °C oven
a 200 °C copper coin in a beaker of water at 98 °C
A bicyclist is riding at a constant speed along a straight-line path. The rider throws a ball straight up to a height a few meters above her head. Ignoring air resistance, where will the ball land? A.in the opposite hand to the one that threw it B.in the same hand that threw the ball C.behind the rider D.This cannot be determined without knowing the speed of the rider and the maximum height of the ball. E.in front of the rider
in the same hand that threw the ball
Which one of the following terms is used to indicate the natural tendency of an object to remain at rest or in motion at a constant speed along a straight line? A.velocity B.inertia C.force D.equilibrium E.acceleration
inertia
With one exception, each of the following units can be used to express mass. What is the exception? A.kilogram B.gram C.newton D.slug E.N•s2/m
newton
Which force is responsible for holding a car in an unbanked curve? A.the horizontal component of the normal force B.the car's weight C.the reaction force to the car's weight D.the vertical component of the normal force E.the force of friction
the force of friction
Airplane One flies due east at 250 km/h relative to the ground. At the same time, Airplane Two flies 325 km/h, 35° north of east relative to the ground. What is the velocity of Airplane One relative to Airplane Two? A.190 km/h, 85° south of west B.210 km/h, 55° south of east C.170 km/h, 15° north of east D.16 km/h, due west E.270 km/h, due north
190 km/h, 85° south of west
On a cold day (-3 °C), the gauge pressure on a tire is 2.0 atm. If the tire is heated to 27 °C, without changing its volume, what will the gauge pressure be? A.2.9 atm B.2.3 atm C.3.3 atm D.27 atm E.2.1 atm
2.3 atm
Two moles of a monatomic gas with an rms speed of 294 m/s are contained in a tank that has a volume of 0.12 m 3. If each gas particle has a mass of 8.220 × 10 -26 kg, what is the absolute pressure of the gas? A.2.1 × 105 Pa B.2.4 × 104 Pa C.4.8 × 104 Pa D.1.1 × 104 Pa E.3.0 × 104 Pa
2.4 × 104 Pa
A 7.50 × 10 -3-m 3 bottle contains 0.0200 kg of oxygen gas, O 2, at 77.0 °C. What is the pressure exerted on the inner walls of the flask by the oxygen gas? Note: the atomic mass of O is 15.9994 u. A.2.43 × 105 Pa B.1.45 × 105 Pa C.8.42 × 104 Pa D.1.46 × 106 Pa E.4.86 × 105 Pa
2.43 × 105 Pa
The radius of the earth is 6400 km. An incoming meteorite approaches the earth along the trajectory shown. The point C in the figure is 6400 km above the earth's surface. The point A is located at the earth's center. At point C, what acceleration would the meteorite experience due to the earth's gravity? A.2.5 m/s2 toward A B.9.8 m/s2 toward A C.5.0 m/s2 toward B D.2.5 m/s2 toward B E.5.0 m/s2 toward A
2.5 m/s2 toward A
A concentration difference of a certain solute of 1.0 × 10 -2 kg/m 3 is maintained between the ends of a tube with a length of 3.5 m and a cross-sectional area of 0.25 m 2. When 0.0040 g of the solute is introduced to the tube, it takes 350 minutes for this solute to diffuse through the solvent to the opposite end of the tube. What is the diffusion constant for the solute? A.1.1 × 10-11 m2/s B.2.7 × 10-7 m2/s C.7.5 × 10-10 m2/s D.6.3 × 10-8 m2/s E.4.5 × 10-9 m2/s
2.7 × 10-7 m2/s
A 0.25-kg ball attached to a string is rotating in a horizontal circle of radius 0.5 m. If the ball revolves twice every second, what is the tension in the string? A.10 N B.5 N C.7 N D.20 N E.2 N
20 N
The ends of a cylindrical steel rod are maintained at two different temperatures. The rod conducts heat from one end to the other at a rate of 10 cal/s. At what rate would a steel rod twice as long and twice the diameter conduct heat between the same two temperatures? A.20 cal/s B.40 cal/s C.5 cal/s D.10 cal/s E.80 cal/s
20 cal/s
Two cars A and B approach each other at an intersection. Car A is traveling south at 20 m/s, while car B is traveling east at 17 m/s. What is the velocity of car A as described by the passengers in car B? A.26 m/s, 50° south of west B.37 m/s, eastward C.26 m/s, 50° south of east D.26 m/s, 40° south of west E.26 m/s, 40° south of east
26 m/s, 50° south of west
A satellite in orbit around the earth has a period of one hour. An identical satellite is placed in an orbit having a radius that is nine times larger than that of the first satellite. What is the period of the second satellite? A.4 h B.3 h C.9 h D.27 h E.0.04 h
27 h
A 975-kg car accelerates from rest to 26.7 m/s in a distance of 120 m. What is the magnitude of the average net force acting on the car? A.2900 N B.1300 N C.91 N D.7900 N E.740 N
2900 N
The power radiated by a distant star is 6.2 × 10 27 W. The radius of the star, which may be considered a perfect radiator, is 1.06 × 10 10 m. Determine the surface temperature of the star. A.8710 K B.2970 K C.9970 K D.7440 K E.4630 K
2970 K
A cabin has a 0.159-m thick wooden floor [ k = 0.141 W/(m · C°)] with an area of 13.4 m 2. A roaring fire keeps the interior of the cabin at a comfortable 18.0 °C while the air temperature in the crawl space below the cabin is -16.4 °C. What is the rate of heat conduction through the wooden floor? A.138 J/s B.408 J/s C.19 J/s D.459 J/s E.264 J/s
408 J/s
A quarterback throws a pass at an angle of 35° above the horizontal with an initial speed of 25 m/s. The ball is caught by the receiver 2.55 seconds later. Determine the distance the ball was thrown. A.13 m B.52 m C.72 m D.18 m E.36 m
52 m
Assume that the sun is a sphere of radius 6.96 × 10 8 m and that its surface temperature is 5.8 × 10 3 K. If the sun radiates at a rate of 3.90 × 10 26 W and is a perfect emitter, at what rate is energy emitted per square meter at the sun's surface? A.12.8 × 107 W/m2 B.5.6 × 1017 W/m2 C.25.6 × 107 W/m2 D.5.6 × 107 W/m2 E.6.4 × 107 W/m2
6.4 × 107 W/m2
Water is flowing through a rectangular channel that is 12 m wide with a speed of 0.75 m/s. The water then flows into four identical rectangular channels that have a width of 3.0 m. The depth of the water does not change as it flows into the four channels. What is the speed of the water in one of the smaller channels? A.0.75 m/s B.3.0 m/s C.0.56 m/s D.2.3 m/s E.0.25 m/s
A.0.75 m/s
A 2.0-kg object is attached to a spring ( k = 55.6 N/m) that hangs vertically from the ceiling. The object is displaced 0.045 m vertically. When the object is released, the system undergoes simple harmonic motion. What is the magnitude of the maximum acceleration of the object? A.1.3 m/s2 B.4.4 m/s2 C.11 m/s2 D.9.8 m/s2 E.2.3 m/s2
A.1.3 m/s2
An engineer is asked to design a playground slide such that the speed a child reaches at the bottom does not exceed 6.0 m/s.Determine the maximum height that the slide can be. A.1.8 m B.4.5 m C.2.9 m D.3.2 m E.7.4 m
A.1.8 m
A 45-N brick is suspended by a light string from a 2.0-kg pulley. The brick is released from rest and falls to the floor below as the pulley rotates through 5.0 rad. The pulley may be considered a solid disk of radius 1.5 m. What is the angular speed of the pulley? A.17 rad/s B.7.3 rad/s C.9.4 rad/s D.15 rad/s E.8.1 rad/s
A.17 rad/s think this is wrong, but answer marked correct online
A 1500-kg satellite orbits a planet in a circular orbit of radius 6.2 × 10 6 m. What is the angular momentum of the satellite in its orbit around the planet if the satellite completes one orbit every 1.5 × 10 4 s? A.2.4 × 1013 kg ⋅ m2/s B.8.1 × 1011 kg ⋅ m2/s C.1.4 × 1014 kg ⋅ m2/s D.6.2 × 108 kg ⋅ m2/s E.3.9 × 106 kg ⋅ m2/s
A.2.4 × 1013 kg ⋅ m2/s
A string is tied to a doorknob 0.72 m from the hinge as illustrated in the figure. At the instant shown, the force applied to the string is 5.0 N. What is the magnitude of the torque on the door? A.3.0 N ⋅ m B.0.78 N ⋅ m C.0.60 N ⋅ m D.2.1 N ⋅ m E.1.0 N ⋅ m
A.3.0 N ⋅ m
In which one of the following situations is linear momentum not conserved? A.A tree limb is struck by lightning and falls to the ground. B.A golf ball is struck by a club. C.A bowling ball collides with a set of ten pins. D.An astronaut floating in space throws a hammer away and subsequently moves in the opposite direction. E.A bomb suspended by a string explodes into one hundred fragments.
A.A tree limb is struck by lightning and falls to the ground.
The coefficient of linear expansion of steel is 12 × 10 -6/C°. A railroad track is made of individual rails of steel 1.0 km in length. By what length would these rails change between a cold day when the temperature is -10 °C and a hot day at 30 °C? A.480 cm B.0.62 cm C.48 cm D.24 cm E.620 cm
C.48 cm
Complete the following statement: The angular measure 1.0 radian is equal to A.1.57°. B.3.14°. C.57.3°. D.6.28°. E.0.0175°.
C.57.3°.
A vertical block-spring system on earth has a period of 6.0 s. What is the period of this same system on the moon where the acceleration due to gravity is roughly 1/6 that of earth? A.15 s B.1.0 s C.6.0 s D.2.4 s E.36 s
C.6.0 s
A 5.00-kg block of ice is sliding across a frozen pond at 2.00 m/s. A 7.60-N force is applied in the direction of motion. After the ice block slides 15.0 m, the force is removed. The work done by the applied force is A.-114 J. B.+19.7 J. C.+114 J. D.-735 J. E.+735 J.
C.+114 J.
A 0.015-kg marble moving to the right at 0.40 m/s has a head-on, elastic collision with a 0.045-kg marble sitting at rest on a smooth, level surface. Which of the following are the correct magnitudes and directions of the velocities of the two marbles after the collision? 0.015 kg marble 0.045 kg marble A.0.40 m/s, left zero m/s B.zero m/s 0.25 m/s, right C.0.20 m/s, left 0.20 m/s, right D.0.10 m/s, right 0.30 m/s, right E.0.15 m/s, left 0.25 m/s, right
C.0.20 m/s, left 0.20 m/s, right
A ball hung from a vertical spring oscillates in simple harmonic motion with an angular frequency of 2.6 rad/s and an amplitude of 0.075 m. What is the maximum acceleration of the ball? A.0.13 m/s2 B.2.6 m/s2 C.0.51 m/s2 D.0.20 m/s2 E.35 m/s2
C.0.51 m/s2
At standard temperature and pressure, carbon dioxide has a density of 1.98 kg/m 3. What volume does 1.70 kg of carbon dioxide occupy at standard temperature and pressure? A.1.7 m3 B.0.43 m3 C.0.86 m3 D.4.8 m3 E.2.3 m3
C.0.86 m3
Joe is painting the floor of his basement using a paint roller. The roller has a mass of 2.4 kg and a radius of 3.8 cm. In rolling the roller across the floor, Joe applies a force F = 16 N directed at an angle of 35° as shown. Ignoring the mass of the roller handle, what is the magnitude of the angular acceleration of the roller? A.2.3 × 102 rad/s2 B.2.8 × 102 rad/s2 C.1.0 × 102 rad/s2 D.1.7 × 102 rad/s2 E.7.2 × 101 rad/s2
C.1.0 × 102 rad/s2
A thin, circular disc is made of lead and has a radius of 0.0350 cm at 20.0 °C. Determine the change in the area of the circle if the temperature is increased to 625.0 °C. The coefficient of linear thermal expansion for lead is 29.0 × 10 -6/C°. A.5.92 × 10-4 cm2 B.3.19 × 10-4 cm2 C.1.36 × 10-4 cm2 D.4.33 × 10-5 cm2 E.1.89 × 10-4 cm2
C.1.36 × 10-4 cm2
A 60.0-kg skater begins a spin with an angular speed of 6.0 rad/s. By changing the position of her arms, the skater decreases her moment of inertia to one-half its initial value. What is the skater's final angular speed? A.4.5 rad/s B.18 rad/s C.12 rad/s D.3.0 rad/s E.9.0 rad/s
C.12 rad/s
A certain spring compressed 0.20 m has 10 J of elastic potential energy. The spring is then cut into two halves and one of the halves is compressed by 0.20 m. How much potential energy is stored in the compressed half of the spring? A.40 J B.14 J C.20 J D.5 J E.10 J
C.20 J
How much power is needed to lift a 75-kg student vertically upward at a constant speed of 0.33 m/s? A.115 W B.25 W C.243 W D.12.5 W E.230 W
C.243 W
A wheel turns through an angle of 188 radians in 8.0 s; and its angular speed at the end of the period is 44 rad/s. If the angular acceleration is constant, what was the angular speed of the wheel at the beginning of the 8.0 s interval? A.9.1 rad/s B.23.5 rad/s C.3.0 rad/s D.32.5 rad/s E.7.0 rad/s
C.3.0 rad/s
What is the minimum amount of energy required to completely melt a 7.25-kg lead brick which has a starting temperature of 18.0 °C? The melting point of lead is 328 °C. The specific heat capacity of lead is 128 J/(kg · C°); and its latent heat of fusion is 23 200 J/kg. A.2.88 × 105 J B.1.68 × 105 J C.4.56 × 105 J D.1.20 × 105 J E.7.44 × 105 J
C.4.56 × 105 J
A ping-pong ball weighs 0.025 N. The ball is placed inside a cup that sits on top of a vertical spring. If the spring is compressed 0.055 m and released, the maximum height above the compressed position that the ball reaches is 2.84 m. Neglect air resistance and term-4determine the spring constant. A.11 N/m B.5.2 N/m C.47 N/m D.2.6 N/m E.24 N/m
C.47 N/m
Oil ( ρ = 925 kg/m 3) is flowing through a pipeline at a constant speed when it encounters a vertical bend in the pipe raising it 4.0 m. The cross sectional area of the pipe does not change. What is the difference in pressure ( P B - P A) in the portions of the pipe before and after the rise? A.-7.2 × 105 Pa B.+5.1 × 105 Pa C.-1.8 × 103 Pa D.-3.6 × 104 Pa E.+2.4 × 104 Pa
D.-3.6 × 104 Pa
Ryan places 0.150 kg of boiling water in a thermos bottle. How many kilograms of ice at -12.0 °C must Ryan add to the thermos so that the equilibrium temperature of the water is 75.0 °C? A.0.0265 kg B.0.625 kg C.0.0713 kg D.0.0233 kg E.0.0436 kg
D.0.0233 kg
While a car is stopped at a traffic light in a storm, raindrops strike the roof of the car. The area of the roof is 5.0 m 2. Each raindrop has a mass of 3.7 × 10 -4 kg and speed of 2.5 m/s before impact and is at rest after the impact. If, on average at a given time, 150 raindrops strike each square meter, what is the impulse of the rain striking the car? A.0.14 N ⋅ s B.0.046 N ⋅ s C.11 N ⋅ s D.0.69 N ⋅ s E.21 N ⋅ s
D.0.69 N ⋅ s
A meter stick is pivoted at the 0.50-m line. A 3.0-kg object is hung from the 0.15-m line. Where should a 5.0-kg object be hung to achieve equilibrium (the meter stick oriented horizontal and motionless)? A.0.06-m line B.0.56-m line C.0.24-m line D.0.71-m line E.A 5.0-kg object cannot be placed anywhere on the meter stick to result in equilibrium in this system.
D.0.71-m line
A pendulum is transported from sea-level, where the acceleration due to gravity g is 9.80 m/s 2, to the bottom of Death Valley. At this location, the period of the pendulum is decreased by 3.00%. What is the value of g in Death Valley? A.9.51 m/s2 B.9.22 m/s2 C.9.80 m/s2 D.10.4 m/s2 E.10.1 m/s2
D.10.4 m/s2
A 1000-kg car traveling east at 20 m/s collides with a 1500-kg car traveling west at 10 m/s. The cars stick together after the collision. What is the common velocity of the cars after the collision? A.16 m/s, east B.6 m/s, west C.4 m/s, east D.2 m/s, east E.1 m/s, west
D.2 m/s, east
Consider four point masses located as shown in the sketch. The acceleration due to gravity is the same everywhere. What is the x coordinate of the center of gravity for this system? A.3.3 m B.2.7 m C.2.0 m D.3.0 m E.3.8 m
D.3.0 m
A solid sphere of radius R rotates about a diameter with an angular speed ω. The sphere then collapses under the action of internal forces to a final radius R/2. What is the final angular speed of the sphere? A.ω/4 B.ω/2 C.ω D.4ω E.2ω
D.4ω
An ice cube, ρ = 917 kg/m 3, is sliding down a frictionless incline as shown in the drawing. The sides of the cube each have a length of 0.75 m. What pressure does the cube exert on the incline? A.5100 Pa B.1800 Pa C.2700 Pa D.6500 Pa E.3600 Pa
D.6500 Pa
A motorist driving a 1000-kg car wishes to increase her speed from 20 m/s to 30 m/s in 5 s. Determine the horsepower required to accomplish this increase. Neglect friction. A.30 hp B.20 hp C.90 hp D.70 hp E.80 hp
D.70 hp
A circular hula hoop rolls upright without slipping on a flat horizontal surface. Which one of the following statements is necessarily true? A.All points on the rim of the hoop have the same speed. B.All points on the rim of the hoop have acceleration vectors that are tangent to the hoop. C.All points on the rim of the hoop have the same velocity. D.Every point on the rim of the wheel has a different velocity. E.All points on the rim of the hoop have acceleration vectors that point toward the center of the hoop.
D.Every point on the rim of the wheel has a different velocity.
Three thermometers are in the same water bath. After thermal equilibrium is established, it is found that the Celsius thermometer reads 0 °C, the Fahrenheit thermometer reads 12 °F, and the Kelvin thermometer reads 273 K. Which one of the following statements is the most reasonable conclusion? A.All three thermometers are incorrect. B.The Celsius thermometer is incorrect. C.The Kelvin thermometer is incorrect. D.The Fahrenheit thermometer is incorrect. E.The three thermometers are at different temperatures.
D.The Fahrenheit thermometer is incorrect.
A rock is dropped from a high tower and falls freely under the influence of gravity. Which one of the following statements concerning the rock as it falls is true? Neglect the effects of air resistance. A.The rock will gain an equal amount of kinetic energy during each second. B.The rock will gain an equal amount of speed for each meter through which it falls. C.The amount of momentum the rock gains will be proportional to the amount of potential energy that it loses. D.The rock will gain an equal amount of momentum during each second. E.The rock will gain an equal amount of momentum for each meter through which it falls.
D.The rock will gain an equal amount of momentum during each second.
A rigid body rotates about a fixed axis with a constant angular acceleration. Which one of the following statements is true concerning the tangential acceleration of any point on the body? A.The tangential acceleration is constant in both magnitude and direction. B.The tangential acceleration depends on the angular velocity. C.The tangential acceleration is equal to the centripetal acceleration. D.The tangential acceleration depends on the change in the angular velocity. E.The tangential acceleration is zero m/s2.
D.The tangential acceleration depends on the change in the angular velocity.
A 0.065-kg tennis ball moving to the right with a speed of 15 m/s is struck by a tennis racket, causing it to move to the left with a speed of 15 m/s. If the ball remains in contact with the racquet for 0.020 s, what is the magnitude of the average force exerted on the ball? A.160 N B.zero newtons C.320 N D.240 N E.98 N
E.98 N
A grindstone of radius 4.0 m is initially spinning with an angular speed of 8.0 rad/s. The angular speed is then increased to 12 rad/s over the next 4.0 seconds. Assume that the angular acceleration is constant.Reference: Ref 8-1What is the average angular speed of the grindstone? A.2.0 rad/s B.8.0 rad/s C.4.0 rad/s D.0.5 rad/s E.10 rad/s
E.10 rad/s
The velocity of a certain simple harmonic oscillator is given by v = -(12 m/s) sin [(6.0 rad/s) t]. What is the amplitude of the simple harmonic motion? A.8.0 m B.12 m C.6.0 m D.4.0 m E.2.0 m
E.2.0 m
The brick shown in the drawing is glued to the floor. A 3500-N force is applied to the top surface of the brick as shown. If the brick has a shear modulus of 5.4 × 109 N/m 2, how far to the right does the top face move relative to the stationary bottom face? A.6.5 × 10-7 m B.3.4 × 10-7 m C.5.8 × 10-6 m D.1.1 × 10-6 m E.2.6 × 10-6 m
E.2.6 × 10-6 m
A fan rotating with an initial angular velocity of 1000 rev/min is switched off. In 2 seconds, the angular velocity decreases to 200 rev/min. Assuming the angular acceleration is constant, how many revolutions does the blade undergo during this time? A.10 B.1200 C.125 D.100 E.20
E.20
A 1.0-m roulette wheel reaches a maximum angular speed of 18 rad/s before it begins decelerating. After reaching this maximum angular speed, it turns through 35 revolutions (220 rad) before it stops. How long did it take the wheel to stop after reaching its maximum angular speed? A.8.8 s B.3.7 s C.12 s D.48 s E.24 s
E.24 s
The graph shows the equilibrium vapor pressure versus temperature for a certain liquid and its vapor within an open container. If the container is at sea level, at approximately what temperature will the liquid boil? A.100 °C B.50 °C C.85 °C D.65 °C E.75 °C
E.75 °C
In which one of the following situations is zero net work done? A.A ball rolls down an inclined plane. B.A projectile falls toward the surface of Earth. C.A physics student stretches a spring. D.A child pulls a toy across a rough surface causing it to accelerate. E.A box is pulled across a rough floor at constant velocity.
E.A box is pulled across a rough floor at constant velocity.
Which one of the following statements concerning momentum is true? A.The momentum of an object is always positive. B.The SI unit of momentum is kg ⋅ m2/s. C.Momentum is a scalar quantity. D.Momentum is a force. E.Momentum and impulse are measured in the same units.
E.Momentum and impulse are measured in the same units.
The figure shows two fish tanks, each having ends of width 1 foot. Tank A is 3 feet long while tank B is 6 feet long. Both tanks are filled with 1 foot of water. S A = the magnitude of the force of the water on the end of tank A S B = the magnitude of the force of the water on the end of tank B B A = the magnitude of the force of the water on the bottom of tank A B B = the magnitude of the force of the water on the bottom of tank BUsing the notation given above, which one of the following sets of equations below is correct for this situation? A.SA = 2SB and BA = 2BB B.SA = SB and BA = BB C.SA = 2SB and BA = BB D.2SA = SB and 2BA = BB E.SA = SB and 2BA = BB
E.SA = SB and 2BA = BB
Two cubes, one silver and one iron, have the same mass and temperature. A quantity Q of heat is removed from each cube. Which one of the following properties causes the final temperatures of the cubes to be different? A.coefficient of volume expansion B.latent heat of vaporization C.volume D.density E.specific heat capacity
E.specific heat capacity
