Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
AP PHYSICS Mr. Brennan Cudd [email protected] The attached work is due back to Azle High School by: June 8th 10:00 – 12:00 & 1:00 – 3:00 Work will not be accepted after the dates listed above. If you are out of town on the above listed dates, all assignments must be submitted to the AHS Counseling office prior to June 8th. Summer counseling office hours are 7:30 - 11:30 am & 12:30 – 4:00 pm Mr. Brennan Cudd Attach this completed form to the front of summer work. Student Name:___________________________________________ Student Email:___________________________________________ Parent Name:_____________________________________________ Parent Email:_____________________________________________ Parent Phone Number:______________________________________ 2017 AP Physics Summer Work Dear AP Physics prospective student: This document has four different assignments covering four topics. On Shayna Reasoner’s school webpage you will find these same assignments plus a PowerPoint in PDF format that you are more than welcome to download in assisting you in learning about the topics covered in the four assignments. The four assignments cover: (1) Rotational Mechanics – Torque (2) Rotational Mechanics – Dynamics (3) Rotational Mechanics – Angular Momentum (4) Universal Gravitation WEBSITE: The website can be found from the Azle High School home page: Go to www.azleisd.net Click on “Select a School” at the top Choose Azle High School Click on “Staff and Organizations” Click on the name (Shayna Reasoner) AP Physics Summer Work can be accessed from the left-hand menu. In completing the assignments, please write your answers in the answer blanks in capital letters and then bubble in the answers on the Scantron cards that are provided (4). It is very important that you turn in BOTH the Scantron cards as well as this packet. Also note that if you come up with an answer that is not listed as a possible answer, please leave the answer blank on the Scantron card and write what you think is the correct answer on the summer worksheet. The attached work is due back to Azle High School by: June 8th 10:00 – 12:00 & 1:00 – 3:00 Work will not be accepted after the dates listed above. If you are out of town on the above listed dates, all assignments must be submitted to the AHS Counseling office prior to June 8th. Summer counseling office hours are 7:30 - 11:30 am & 12:30 – 4:00 pm Name __________________________________________ AP Physics Summer Work Rotational Mechanics – Torque (1) For Questions 1 – 5, A = True & B = False The distance between a turning axis and the point of contact of a perpendicular force is called the fulcrum. 1) ______ (2) Torque is the product of a force exerted on an object times the lever arm. 2) ______ (3) In order for a seesaw to be in rotational equilibrium, the sum of the torques acting on it need not be balanced if one person sits closer to the fulcrum than the other person. 3) ______ (4) Torque is defined as tangential force times mass. 4) ______ (5) Suppose you try loosening a nut with a wrench, and the nut doesn't give at all. You increase 5) ______ your chance of success if you exert a larger force. (6) A heavy boy and a light girl are balanced on a mass-less seesaw. If they both move forward so that they are one-half their original distance from the pivot point, what will happen to the seesaw? A) The side the girl is sitting on will tilt downward. B) The side the boy is sitting on will tilt downward. C) The seesaw will start rotating counter-clockwise. D) Nothing, the seesaw will still be balanced. 6) ______ (7) A vault is opened by applying a force of 300 N perpendicular to the plane of the door, 0.8 m from the hinges. Find the torque due this force about an axis through the hinges. A) 120 N-m B) 240 N-m C) 300 N-m D) 360 N-m 7) ______ (8) A meter stick is supported by a knife edge at the 0.5 m mark. Ryan hangs masses of 0.40 kg and 0.60 kg from the 0.2 m and 0.8 m marks, respectively. Where should Ryan hang a third mass of 0.30 kg to keep the stick balanced (rotational equilibrium)? A) 0.15 m B) 0.20 m C) 0.25 m D) 0.30 m 8) ______ (9) Two equal forces are applied to a door. The first force is applied at the midpoint of the door; the second force is applied at the doorknob. Both forces are applied perpendicular to the door. Which force exerts the greater torque? A) both exert equal non-zero torques B) the first at the midpoint C) the second at the doorknob D) both exert zero torques 9) ______ Page 2 (10) The bolts on a car wheel require tightening to a torque of 90 Nm. If a 0.3-m long wrench is used, what is the magnitude of the force required when the force is perpendicular to the wrench? A) 150 N B) 30 N C) 300 N D) 15 N 10) ______ (11) A 60-kg boy sits on a seesaw 1.0 m from the fulcrum. What distance from the fulcrum should a 30-kg girl should sit in order to balance the seesaw? A) 1.3 m B) 2.0 m C) 2.5 m D) 3.0 m 11) ______ (12) Mary pushes a metal pipe 1.5 m out past the edge of a building so that it is just perfectly 12) ______ balanced from tipping over while a basket weighing 100 N hangs on the end. If the uniform pipe weighs 200 Newtons how far away from the edge is the center of gravity of the pipe located? A) 0.50 m B) 0.75 m C) 1.25 m D) 1.50 m (13) A bucket filled with water has a mass of 23 kg and is attached to a rope that is wound around a cylinder with a diameter of 0.10 meters at the top of the well. What torque does the weight of the water and bucket produce on the cylinder? (g = 9.8 m/s2) A) 34 N – m B) 23 N – m C) 17 N – m D) 11 N – m 13) ______ Page 3 (14) Jack and Jill are sitting on opposite sides of a seesaw; each 2 meters from the fulcrum. If Jack has a mass of 60 kg and Jill has a mass of 50 kg how far can Mighty Mutt (mass = 25 kg) sit from Jill so that all are in rotational equilibrium? A) 0.8 m B) 1.0 m C) 1.2 m D) 1.6 m 14) ______ (15) If a clockwise force is applied a perpendicular distance from a pivot point in the plane of this paper, what is the direction of the resultant torque vector? A) clockwise B) toward the top of this paper C) perpendicular and into the paper D) perpendicular and out of the paper 15) ______ (16) A uniform board that weighs 500 N is supported by two bricks. Two bricks, one at each 16) ______ end of the board, support the board. If the board is 3 meters long and a sack of sand weighing 400 Newtons is located 0.5 meters from the middle of the board, how much weight does each brick support? A) 900 N and 517 N B) 383 N and 517 N C) 383 N and 450 N D) 1550 N and 900 N (17) Morgan and Abby have a uniform pole that is 2 meters long and weighs 50 Newtons. The girls are to carry a 100 Newton backpack hanging from the pole from one class to another. While Morgan isn’t looking Abby shifts the backpack so that the backpack is only 75 cm (0.75 m) from Morgan. If the ends of the pole are supported by the girls how much weight does Morgan carry? A) 87.5 N B) 62.5 N C) 150 N D) 75.0 N 17) ______ Page 4 (18) A utility pole that lies on the ground weighs 4000 Newtons is non-uniform and 10 m long. 18) ______ If the center of mass for the pole is 2 meters from the heavier end and Carl wants to pick up the lighter end of the pole, what is the minimum force he will have to use? A) 4000 N B) 100 N C) 500 N D) 800 N (19) When Kin opens a door for his mother he pulls the door handle with a force of 20 Newtons. 19) ______ If his arms make a 30 angle with the door and the door handle is 0.9 meters from the door hinges, how much torque does Kin exert on the door? A) 9 N – m B) 45 N – m C) 4.5 N – m D) 16 N – m (20) A pulley with a diameter of 20 centimeters has a 500 gram mass tied to a string that passes over the pulley and is just hanging. What torque is the mass exerting on the pulley? A) 9.8 N – m B) 0.98 N – m C) 490 N – m D) 0.49 N – m 20) ______ Name __________________________________________ AP Physics Summer Work Rotational Mechanics – Dynamics (1) Two uniform solid spheres, A and B have the same mass. The radius of sphere B is twice that of sphere A. The axis of rotation passes through the center of each sphere. Which one of the following statements concerning the moments of inertia of these spheres is true? A) The moment of inertia of A is one-fourth that of B. B) The moment of inertia of A is one-half that of B. C) The moment of inertia of A is 5/4 that of B. D) The moment of inertia of A is 5/8 that of B. 1) ______ (2) A slender 1.5-m rod, with mass 1.25-kg, is rotated about the perpendicular axis through its center. What is its resistance to this rotation? A) 0.938 kg - m2 B) 0.234 kg - m2 C) 1.88 kg - m2 D) 2.81 kg - m2 2) ______ (3) A 0.250-kg rubber stopper is attached to a 0.50-m long string. What is its moment of inertia 3) ______ as it twirls around a horizontal circle? A) 0.0313 kg - m2 B) 0.0125 kg - m2 C) 0.0625 kg - m2 D) 313,000 kg - m2 (4) A pulley, with a radius of 0.025-m, has a rotational inertia of 1.75105 kg-m2. What is the 4) ______ mass of the pulley? A) 0.169 kg B) 0.0844 kg C) 0.0560 kg D) 0.0280 kg (5) When a net torque is applied to a rigid object, it always produces a A) constant acceleration. B) rotational equilibrium. C) constant angular velocity. D) change in angular velocity. 5) ______ (6) A bicycle wheel, a hollow sphere, and a solid sphere each have the same mass and radius. They each rotate about an axis through their centers. Which has the greatest moment of inertia and which has the least? A) The wheel has the greatest; the hollow sphere has the least. B) The wheel has the greatest; the solid sphere has the least. C) The hollow sphere has the greatest; the solid sphere has the least. D) The hollow sphere has the greatest; the wheel has the least. E) The solid sphere has the greatest; the hollow sphere has the least. 6) ______ Page 2 – Rotational Dynamics (7) You are given two hoops (I = mR2), which are (1) brass and (2) wood, and two 7) ______ 2 cylinders (I = ½ mR ), which are (3) brass and (4) wood; each has radius R. If all are released from the same starting line at the same time, the one(s) that reach the bottom first are A) 1 and 2 B) 3 and 4 C) 1, 2, 3, and 4 D) 1 E) 3 (8) Starting from rest at the same time, a coin and a ring roll down an incline without slipping. Which reaches the bottom first? A) The ring reaches the bottom first. B) The coin reaches the bottom first. C) They arrive at the bottom simultaneously. D) The winner depends on the relative masses of the two. E) The winner depends on the relative diameters of the two. 8) ______ (9) To increase the moment of inertia of a body about an axis, you must A) increase the angular acceleration. B) increase the angular velocity. C) decrease the angular velocity. D) make the body occupy less space. E) place part of the body farther from the axis. 9) ______ (10) The rotational inertia of an object about an axis depends on the A) angular velocity about the axis. B) torque about the axis. C) angular acceleration about the axis. D) linear acceleration about the axis. E) mass distribution about the axis. 10) ______ (11) A string is wrapped around a pulley of radius 0.10 m and moment of inertia 0.15 kg - m2. The string is pulled with a force of 12 N. What is the magnitude of the resulting angular acceleration of the pulley? A) 18 rad/s2 B) 0.13 rad/s2 C) 0.055 rad/s2 D) 8.0 rad/s2 11) ______ Page 3 – Rotational Dynamics (12) A 2.0 kg rock is tied to a 0.50 m long string and swung around in a circle with a constant 12) ______ angular velocity of 12 rads/s. What is the net torque on the rock about the center of the circle? A) 72 N - m B) 6.0 N - m C) 0 N - m D) 12 N - m (13) A string is wrapped around a pulley of radius 0.05 m and rotational inertia of 0.2 kg - m2. If the string is pulled with a force F, and the resulting angular acceleration of the pulley is 2 rads/s2, what is the magnitude of F? A) 0.4 N B) 2 N C) 8 N D) 16 N 13) ______ (14) A 50 N - m torque acts on a wheel of rotational inertia 150 kg - m2. If the wheel starts from rest, how long will it take the wheel to make one revolution? A) 0.33 second B) 0.66 second C) 2.4 seconds D) 6.1 seconds 14) ______ (15) Jacob starts to push a merry-go-round, initially at rest, with a tangent-to-the-merry-go-round 15) ______ force of 50 Newtons. The merry-go-round has a mass of 200 kg and a radius of 2.0 meters. What is the angular acceleration of the merry-go-round, assuming no friction and the force is constant? A) 0.250 rads/sec2 B) 0.125 rads/sec2 C) 0.500 rads/sec2 D) 0.0625 rads/sec2 (16) A wheel with a moment of inertia 2.00 kg∙m2 has a net torque of 2.50 N-m applied to it. What angular acceleration does it experience? A) 0.200 rads/sec2 B) 1.25 rads/sec2 C) 2.00 rads/sec2 D) 2.50 rads/sec2 16) ______ Page 4 – Rotational Dynamics (17) The drive chain in a bicycle is applying a torque of 0.850 N-m to the wheel of the bicycle. Treat the wheel as a hoop with a mass of 0.750 kg and a radius of 0.330 m. What is the angular acceleration of the wheel? A) 20.8 rads/sec2 B) 10.4 rads/sec2 C) 3.43 rads/sec2 D) 1.06 rads/sec2 E) 5.20 rads/sec2 17) ______ (18) When a ceiling fan rotating with an angular speed of 2.65 rad/s is turned off, a frictional 18) ______ torque of 0.12 N-m slows it to a stop in 19.5 seconds. What is the moment of inertia of the fan? A) 0.750 kg - m2 B) 0.883 kg - m2 C) 0.625 kg - m2 D) 4.42 kg - m2 (19) What constant torque, in the absence of friction, must be applied to a wheel to give it an angular velocity of 50 rad/s if it starts from rest and is accelerated for 10 seconds? The moment of inertia of the wheel about its axle is 9.0 kg - m2. A 4.5 N - m B) 9.0 N - m C) 45 N - m D) 30 N - m E) 60 N - m 19) ______ (20) A wheel slows from 20 rad/s to 12 rad/s in 5 s under the influence of a constant frictional torque. In these 5 seconds, the wheel turns through an angle of A) 2.4 rad B) 43 rad C) 60 rad D) 80 rad E) 100 rad 20) ______ Name __________________________________________ AP Physics Summer Work Rotational Mechanics – Angular Momentum (1) If the angular momentum of a system is constant, which of the following statements must be true? A) A constant torque acts on each part of the system. B) Zero net torque acts on each part of the system. C) A constant external torque acts on the system. D) Zero net torque acts on the system. 1) ______ (2) The angular momentum of a flywheel about its axis is 925 kg-m2/s. If its moment of inertia about the same axis is 2.50 kg-m2, its angular velocity is what amount? A) 370 rev/min B) 62 rev/min C) 2210 rad/s D) 370 rad/s 2) ______ (3) To increase the moment of inertia of a body about an axis, you must A) increase the angular acceleration. B) increase the angular velocity. C) make the body occupy less space. D) place part of the body farther from the axis. 3) ______ (4) A 2.0-g particle moves at a constant speed of 3.0 mm/s around a circle of radius 4.0 mm. Find the magnitude of the angular momentum of the particle. A) 2.40 10−6 kg-m2/s B) 2.40 10−3 kg-m2/s C) 2.40 10−8 kg-m2/s D) 2.40 101 kg-m2/s 4) ______ (5) A 2.0-kg particle moves directly eastward at a constant speed of 4.5 m/s along an east-west line. What is the magnitude of its angular momentum about a point that lies 6.0 meters north of the line? A) 54 kg-m2/s B) 90 kg-m2/s C) 27 kg-m2/s D) 12 kg-m2/s 5) ______ Page 2 (6) You stand on a frictionless platform that is rotating at an angular speed of 1.5 rev/s. Your arms are outstretched, and you hold a heavy weight in each hand. The moment of inertia of you, the extended weights, and the platform is 6.0 kg-m2 . When you pull the weights in toward your body, the moment of inertia decreases to 1.8 kg-m2. What is the resulting angular speed of the platform? A) 5 rev/s B) 0.2 rev/s C) 0.5 rev/s D) 3.33 rev/s 6) ______ (7) A skater is spinning at 32.0 rad/s with her arms and legs extended outward. In this position 7) ______ her moment of inertia with respect to the vertical axis about which she is spinning is 45.6 kg-m2. She pulls her arms and legs in close to her body changing her moment of inertia to 17.5kg-m2. What is her new angular velocity? A) 14.6 rads/s B) 83.4 rad/s C) 12.3 rads/s D) 56.0 rad/s (8) Say that NASA planned to put a satellite into a circular orbit around Pluto for studies, but 8) ______ the situation got a little out of hand and the satellite ended up with an elliptical orbit. At its nearest point to Pluto, 6.6106 meters, the satellite zips along at 9,000 meters per second. At its farthest point the satellite is 2.0107 meters. What is its speed at this farthest location? A) 2970 m/s B) 980 m/s C) 3300 m/s D) 2700 m/s (9) Calculate the angular momentum of a phonograph record (LP) rotating at 33 1 /3 rev/min. An LP has a radius of 15 cm and a mass of 150 grams. A) 3.49 10−1 kg-m2/s B) 1.18 10−2 kg-m2/s C) 5.89 10−3 kg-m2/s D) 3.38 10−3 kg-m2/s (10) A cylinder of mass 250 kg and radius 2.60 m is rotating at 4.00 rad/s on a frictionless surface 10) ______ when two more identical nonrotating cylinders fall on top of the first. Because of friction between the cylinders they will eventually all come to rotate at the same rate. What is this final angular velocity? A) 1.33 rads/s B) 7.50 rad/s C) 3.75 rads/s D) 0.75 rad/s 9) ______ Page 3 (11) A person stands, hands at his side, on a platform that is rotating at a rate of 1.3 rev/s. If he raises his arms to a horizontal position, the speed of rotation decreases to 0.80 rev/s. By what factor has the moment of inertia of the person changed? A) 1.3 times more B) 1.6 times more C) 0.62 times more D) 0.62 times less 11) ______ (12) A figure skater can increase her spin rotation rate from an initial rate of 1.0 revolution every 12) ______ 2 seconds to a final rate of 3.0 rev/sec. If her initial moment of inertia was Ii =4.6 kg-m2 what is her final moment of inertia If ? A) 27.6 kg-m2 B) 2.76 kg-m2 C) 0.77 kg-m2 D) 0.17 kg-m2 (13) A 15 gram paper clip is attached to the rim of a phonograph record with a radius of 30 cm spinning at 3.5 rads/sec. What is the magnitude of the paper clip’s angular momentum? A) 1.4 10−3 kg-m2/s B) 4.7 10−3 kg-m2/s C) 1.6 10−2 kg-m2/s D) 3.2 10−1 kg-m2/s (14) The entrance of a science museum features a funnel into which marbles are rolled one at 14) ______ a time. The marbles circle the wall of the funnel, eventually spiraling down into the neck of the funnel. The internal radius of the funnel at the top is 0.54 m. At the bottom, the funnel’s neck narrows to an internal radius of 0.040 m. A 2.510−2 kg marble begins rolling in a large circular orbit around the funnel’s rim at 0.35 rev/s. If it continues moving in a roughly circular path, what will the marble’s angular speed be as it passes through the neck of the funnel? A) 133 rads/s B) 525 rad/s C) 375 rads/s D) 400 rad/s (15) A 15.0 kg turntable with a radius of 25 cm is covered with a uniform layer of dry ice that 15) ______ has a mass of 9.0 kg. The angular speed of the turntable and dry ice is initially 0.75 rads/s, but it increases as the dry ice evaporates. What is the angular speed of the turntable once all the dry ice has evaporated? A) 6.25 rads/s B) 1.2 rad/s C) 0.47 rads/s D) 18.0 rad/s 13) ______ Page 4 (16) Calculate the angular momentum of Earth that arises from its spinning on its axis. (Distance from Sun to Earth is 1.50 x 1011 m; Earth mass = 5.98 x 1024 kg; Sun mass = 1.99 x 1030 kg; Earth radius = 6.37 x 106 m; Sun’s radius = 6.96 x 108 m) A) 7.05 1033 kg-m2/s B) 1.69 1035 kg-m2/s C) 3.25 1034 kg-m2/s D) 5.84 1033 kg-m2/s 16) ______ (17) Calculate the angular momentum of Earth that arises from its orbital motion about the sun. (Distance from Sun to Earth is 1.50 x 1011 m; Earth mass = 5.98 x 1024 kg; Sun mass = 1.99 x 1030 kg; Earth radius = 6.37 x 106 m; Sun’s radius = 6.96 x 108 m) A) 2.66 1044 kg-m2/s B) 1.35 1047 kg-m2/s C) 2.32 1045 kg-m2/s D) 2.68 1040 kg-m2/s 17) ______ (18) A woman sits on a spinning piano stool with her arms folded. When she extends her arms, which of the following occurs? A) She increases her moment of inertia, thereby increasing her angular speed. B) She increases her moment of inertia, thereby decreasing her angular speed. C) She decreases her moment of inertia, thereby increasing her angular speed. D) She decreases her moment of inertia, thereby decreasing her angular speed. 18) ______ (19) A puck on a frictionless air-hockey table has a mass of 0.05 kg and is attached to a cord 19) ______ passing through a hole in the table surface. The puck is originally revolving at a distance of 0.30 m from the hole, with an angular speed 2.50 rads/s. The cord is then pulled from below, shortening the radius of circle in which the puck revolves to 0.10 m. What is the puck’s new angular velocity? A) 7.50 rads/s B) 8.33 rad/s C) 22.5 rads/s D) 27.8 rad/s (20) Suppose that our sun runs out of nuclear fuel and suddenly collapses to form a so-called 20) _____ white dwarf, with a diameter equal to that of Earth. Assuming no mass loss, what would be the sun’s new rotation period (time for one rotation), which is currently about 25 days. A) 2.25 days B) 1.65 hours C) 9.50 min D) 3.01 min Name __________________________________________ AP Physics Summer Work Universal Gravitation (1) The force of gravity is directly proportional to the radial distance between two objects. A) True B) False 1) ______ (2) The value of the universal gravitation constant, G, was discovered by Newton. A) True B) False 2) ______ (3) The universal gravitational constant, G, depends on the distance from the center of earth. A) True B) False 3) ______ (4) The reason the force of gravity controls the motion of planets lies in the fact that the masses 4) ______ involved are very large. A) True B) False (5) The force of gravity is inversely proportional to the radial distance squared between the two 5) ______ objects. A) True B) False (6) If one were to halve the distance between the centers of two objects, the force of gravity between the two objects would be multiplied by four. A) True B) False 6) ______ (7) The force of gravity exerted by the Earth on the Moon is greater than the Moon’s gravitational force on the Earth. A) True B) False 7) ______ (8) Who was the first scientist to see the connection between falling objects, projectiles and satellites in orbit? A) Aristotle B) Galileo C) Sir Isaac Newton D) Copernicus 8) ______ (9) Why does the Earth exert enough gravitational force on our moon to keep it in orbit about the Earth when the sun for our solar system is about a million times more massive than our Earth? A) The moon is pretty small compared to the Earth. B) The centripetal force exerted by the Sun is smaller. C) The Moon has a smaller mass density than the sun. D) The Moon is closer to Earth. 9) ______ (10) On Mars’ surface the robot Curiosity will weigh 1260 Newtons. If the radius of Mars is 3400 km, what will Curiosity weigh 6800 km above the surface of Mars? A) 140 N B) 315 N C) 630 N D) 2520 N 10) ______ Page 2 (11) By what factor would your weight change if the Earth’s diameter were doubled and its mass 11) ______ were also doubled? A) You would weigh one-fourth as much. B) You would weigh twice as much. C) You would weigh four times as much. D) You would weigh one-half as much. (12) If the gravitational forces of the sun on the planets suddenly disappeared in what kind of paths would the planets move? A) The planets would spiral into the sun. B) The planets would fly off radially outward from the sun. C) The planets would fly directly toward the sun. D) The planets would fly off tangentially in straight line paths. 12) ______ (13) Which requires more fuel: sending a rocket from Earth to the Moon or sending the rocket form the Moon to the Earth? A) It takes the same amount of fuel if they travel the same distance each way. B) It takes more fuel to go from the Earth to the Moon because you have to overcome a a greater gravitational force. C) It take more fuel to go from the Moon to the Earth because the Moon is not as massive. D) It takes more fuel to go from Earth to the Moon because the Earth has an atmosphere and the Moon does not. 13) ______ (14) If tides on Earth are caused by gravitational forces when would you expect to see the highest tides? A) When the Moon and the Sun are on the same side of the Earth. B) When the Moon and the Sun are on opposite sides of the Earth. C) When the Sun and the Moon are at right angles to each other with respect to the Earth. D) It does not matter at all where the Moon and the Sun are with respect to the Earth 14) ______ (15) The strength of a gravitational field is sometimes written in terms of force on a single kilogram of mass. In your Physics classroom the gravitational field strength is 9.8 N/kg. What would you expect the gravitational field strength to be one Earth radii above the Earth’s surface? A) 4.9 N/kg B) 2.45 N/kg C) 6.53 N/kg D) 19.6 N/kg 15) ______ (16) If a box on the floor has a mass of 46 kilograms then the earth attracts that mass with a force of A) 1 Newton B) 450 Newtons C) 4500 Newtons D) You cannot calculate the gravitational force without knowing the mass of the Earth. 16) ______ Page 3 (17) A really dense planet has the same mass as the Earth but only one-tenth the radius. What would Haley weigh on this planet if she weighs 400 Newtons on Earth? A) 4000 Newtons B) 40 Newtons C) 4 Newtons D) 40,000 Newtons 17) ______ (18) A 20 Newton force existed between two objects. If one object doubled in mass and the 18) ______ other object tripled in mass while the distance between them halved what would be the new gravitational force between them? A) 120 Newtons B) 48 Newtons C) 60 Newtons D) 480 Newtons (19) If the gravitational field strength at the surface of one planet is 540 Newtons/ kilogram what would the gravitational field strength be one planet diameter above the planet’s surface? A) 270 Newtons/kilogram B) 180 Newtons/kilogram C) 60 Newtons/kilogram D) 90 Newtons/kilogram 19) ______ (20) The average distance between an electron and a proton in a hydrogen atom is 5.31011 m. If the rest mass of an electron is given to be 9.111031 kg and the mass of the proton is given to be 1.671027 kg, what is the gravitational force between the two particles? (Note the universal gravitational constant, G = 6.671011 Nm2/kg2) A) 1.011067 Newtons B) 1.911057 Newtons C) 3.611047 Newtons D) 1.521057 Newtons 20) ______ (21) Calculate the force of gravity between Earth (Mass = 6.0 × 1024 kg) and the Moon (mass = 7.4 × 1022 kg). The average distance between the Earth and Moon is 3.8 × 108 m. A) 2.0×1020 N B) 2.0×1028 N C) 4.4×1022 N D) 4.4×1028 N 21) ______ (22) The mass of an electron is 9.1 × 1031 kg. The mass of a proton is 1.7 × 1027 kg. If the gravitational force of attraction between an electron and a proton in a hydrogen atom is 1.0 × 1047 N, how far apart are the electron and proton? A) 1.0×1020 m B) 1.0×1010 m C) 1.5×1010 m D) 1.5×1020 m 22) ______ Page 4 (23) There is a force on Earth that is directed toward the sun. A) True B) False 23) ______ (24) Because Earth is "falling" around the sun, it will eventually crash into it. A) True B) False 24) ______ (25) The force on a ball decreases as the ball moves farther from Earth. A) True B) False 25) ______ (26) If Earth were its present size but twice as massive, we would weigh less. A) True B) False 26) ______ (27) Because Earth has mass, it also has a gravitational field. A) True B) False 27) ______ (28) Newton had the insight to see that the A) force on the moon has the same nature as the force on an apple. B) moon always keeps one side toward Earth. C) moon is moving. D) moon orbits Earth. 28) ______ (29) Newton did not hypothesized that the moon A) is a projectile. B) is falling around Earth. C) has tangential velocity that prevents it from falling into Earth. D) causes tides on Earth. 29) ______ (30) Newton reasoned that the gravitational attraction between Earth and the moon must be A) directly proportional to distance. B) the same at all distances. C) reduced by distance. D) independent of distance. 30) ______ (31) If the mass of Earth increased, with no change in radius, your weight would A) decrease. B) stay the same. C) increase also. 31) ______ (32) If the radius of Earth decreased, with no change in mass, your weight would A) not change. B) decrease. C) increase. 32) ______ (33) A very massive object A and a less massive object B move toward each other under the of mutual gravitation. Which force, if either is greater? A) The force on A B) The force on B C) Both forces are the same 33) ______