Concept explainers
The century-old ascensores in Valparaiso, Chile, are picturesque cable cars built on stilts to keep the passenger compartments level as they go up and down the steep hillsides. As FIGURE P7-43 show's, one car ascends as the other descends. The cars use a two-cable arrangement to compensate for friction; one cable passing around a large pulley connects the Cars, the second is pulled by a small motor. Suppose the mass of both cars (with passengers) is 1500 kg, the coefficient of rolling friction is 0.020, and the cars move at constant speed. What is the tension in (a) the connecting cable and (b) the cable to the motor?
FIGURE P7.43
Want to see the full answer?
Check out a sample textbook solutionChapter 7 Solutions
Modified Mastering Physics with Pearson eText -- Standalone Access Card -- for Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (4th Edition)
- Imagine 4 objects made of the same material but with different masses. All systems have the same coefficient of static friction μs. Rank in order from smallest to largest: the minimum applied force required to make the objects move if their masses are: Object 1 = m/2 Object 2 = m Object 3 = 2m Object 4 = 4m imagine three objects with the same coefficient of kinetic friction but each having a different mass. We’re going to push each object with a known force F. Rank the velocity of the objects, from smallest to greatest, after we apply the force F for 4 seconds Now think about a robot pushing an object across a horizontal surface without friction and draw graphs for Force, acceleration, velocity, and position all vs. time for both situations. Now think about a robot pushing an object across a horizontal surface with friction and draw graphs for Force, acceleration, velocity, and position all vs. time for both situations.arrow_forwardDetermine the magnitude of the force on the pin at A for the jib crane shown in Figure Q6.a) 55.95 kN b) 18.88 kN c) 26.80 kN d) 42.45 kNarrow_forwardA makeshift sign hangs by a wire that is extended over an ideal pulley and is wrapped around a large potted plant on the roof as shown in Figure P6.10. When first set up by the shopkeeper on a sunny and dry day, the sign and the pot are in equilibrium. Is it possible that the sign falls to the ground during a rainstorm while still remaining connected to the pot? What would have to be true for that to be possible? FIGURE P6.10 Problems 10 and 11.arrow_forward
- Instead of moving back and forth, a conical pendulum moves in a circle at constant speed as its string traces out a cone (Fig. P6.68). One such pendulum is constructed with a string of length L = 12.0cm and bob of mass 0.210 kg. The string makes an angle = 7.00 with the vertical, a. What is the radial acceleration of the bob? b. What are the horizontal and vertical components of the tension force exerted by the string on the bob?arrow_forwardThe starship Enterprise has its tractor beam locked onto some valuable debris and is trying to pull it toward the ship. A Klingon battle cruiser and a Romulan warbird are also trying to recover the item by pulling the debris with their tractor beams as shown in Figure P5.25. a. Given the following magnitudes of the tractor beam forces, find the net force experienced by the debris: FEnt = 7.59 106 N, FRom = 2.53 106 N, and FKling = 8.97 105 N. b. If the debris has a mass of 2549 kg, what is the net acceleration of the debris? FIGURE P5.25arrow_forwardIn the very Dutch sport of Fierljeppen, athletes run up to a long pole and then use it to vault across a canal. At the very top of his arc, a 55 kg vaulter is moving at 2.5 m/s and is 5.1 m from the bottom end of the pole. What vertical force does the pole exert on the vaulter?arrow_forward
- Consider the modified Atwood machine problem illustrated in Example 6.4 on page 274 of the book, and suppose m1 = 5kg and m2 = 10kg . Suppose I apply a horizontal force to the block on the table, so that both masses are at rest. What is the magnitude of the force I should apply? Group of answer choices 6.53 N 0.0 N 32.7 N 98.0 Narrow_forwardTwo blocks, which can be modeled as point masses, are connected by a massless string which passes through a hole in a frictionless table. A tube extends out of the hole in the table so that the portion of the string between the hole and M1 remains parallel to the top of the table. The blocks have masses M1 = 1.2 kg and M2 = 2.7 kg. Block 1 is a distance r = 0.55 m from the center of the frictionless surface. Block 2 hangs vertically underneath. 1) If we Assume that block two, M2, does not move relative to the table and that block one, M1, is rotating around the table. What is the speed of block one, M1, in meters per second?arrow_forwardTwo penguins, Wheezy and Mumble, are racing down an icy slope into the water below. Wheezy has a mass of 22 kg. Mumble has a mass of 25 kg. The slope is angled at eight degrees to the horizontal. They both start from the same position at the same time, and slide down the icy slope entirely due to gravity alone. There is a coefficient of kinetic friction of 0.12 between the penguins and the ice. Who wins the race and what is the winner's acceleration when they reach the finish line (ie the water)?arrow_forward
- A person pulls at an angle of 0 = 34.0° on three connected crates of masses m¡ = 25.0 kg, m2 = 18.0 kg, and Pull m3 = 15.0 kg over a smooth horizontal floor, as shown in A В the figure. The crates are connected to each other by m, m, m3 identical massless, horizontal strings A and B, each of which can support a maximum tension of 45.0 N before breaking. What is the magnitude F, of the largest pulling force that can be exerted without breaking either of the strings?arrow_forwardConsider the Atwood machine shown in the figure, where m1 = 2.00 kg and m2 = 5.00 kg. The system starts at rest, then the sphere is given a quick push downward, giving it an initial speed of 2.45 m/s. Assume the pulley and cord are massless, and the cord is inextensible. Neglect friction. (a)Through what distance (in m) will m1 descend? b)What is the velocity (in m/s) of m1 after 1.80 s? magnitudearrow_forwardA window washer is standing on a scaffold supported by a vertical rope at each end. The scaffold weighs 202 N and is 2.8 m long. What is the tension in each rope when the 706–N worker stands 1.20 m from one end? SMALLER TENSION= _______N LARGER TENSION= ________Narrow_forward
- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningGlencoe Physics: Principles and Problems, Student...PhysicsISBN:9780078807213Author:Paul W. ZitzewitzPublisher:Glencoe/McGraw-Hill
- Physics for Scientists and Engineers, Technology ...PhysicsISBN:9781305116399Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning