47. To meet a U.S. Postal Service requirement, employees' foot wear must have a coefficient of static friction of 0.500 or more on a specified tile surface. A typical athletic shoe has a coef ficient of 0.800. In an emergency, what is the minimum time interval in which a person starting from rest can move 3.00 m on the tile surface if she is wearing (a) footwear meeting the Postal Service minimum and (b) a typical athletic shoe? ~^^

47. To meet a U.S. Postal Service requirement, employees' foot wear must have a coefficient of static friction of 0.500 or more on a specified tile surface. A typical athletic shoe has a coef ficient of 0.800. In an emergency, what is the minimum time interval in which a person starting from rest can move 3.00 m on the tile surface if she is wearing (a) footwear meeting the Postal Service minimum and (b) a typical athletic shoe? ~^^

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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moodle.nct.eduom/mod/qi -Learning Portal Courses - Reports - e-Services- Academic Departments - ETC - CIMS - A 17kg crate resting on a horizontal surface is pushed as shown. If the coefficient of static friction u, between the surfaces is 0.24, what is the minimum force (F) required to start the motion? O a 4.08N O b. 70.83N Oc 39.98N Od. 694.17N Windows buut An object of mass Skg is sliding with a constant velocity of 10m/s on a frcitionless horizontal table. The force needed to keep the object moving with the same velocity is. 144 4- # 4. 6. V.
10. To meet a U.S. Postal Service requirement, employees' footwear must have a coefficient of static friction of 0.5 or more on a specified tile surface. A typical athletic shoe has a coefficient of static friction of 0.800. In an emergency, what is the minimum time interval in which a person starting from rest can move 3.00 m on the tile surface if she is wearing (a) footwear meeting the Postal Service minimum and (b) a typical athletic shoe? Answers: a) 1.11 s b) 0.875 s
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(a) A flatbed truck moving at 28 m/s carries a steel girder that rests on its wooden floor. The girder is not strapped down, in violation with USDOT regulations. If the coefficient of static friction between steel and wood is 0.52, what is the minimum distance over which the truck can come to a stop without the girder sliding toward the cab of the truck? (answer: 77 m) (b) What is the minimum time over which the truck can accelerate forward from 0 m/s to 28 m/s with a constant acceleration without the girder sliding off the back? (answer: 5.5 s)
(a) A flatbed truck moving at 28 m/s carries a steel girder that rests on its wooden floor. The girder is not strapped down, in violation with USDOT regulations. If the coefficient of static friction between steel and wood is 0.52, what is the minimum distance over which the truck can come to a stop without the girder sliding toward the cab of the truck? (answer: 77 m) (b) What is the minimum time over which the truck can accelerate forward from 0 m/s to 28 m/s with a constant acceleration without the girder sliding off the back? (answer: 5.5 s) FNET = ma fs,max = UsN W =mg v² = vo² + 2aAx %3D %3D V = Vo+ at g = 9.81 m/s?
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27. A horse is harnessed to a sled having a mass of 236 kg, includ- ing supplies. The horse must exert a force exceeding 1 240 N at an angle of 35.0° in order to get the sled moving. Treat the sled as a point particle. (a) Calculate the normal force on the sled when the magnitude of the applied force is 1 240 N. (b) Find the coefficient of static friction between the sled and the ground beneath it. (c) Find the static friction force when the horse is exerting a force of 6.20 X 10² N on the sled at the same angle. 3
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The 118-lb force P is applied to the 250-lb crate, which is stationary before the force is applied. Determine the magnitude and direction of the friction force F exerted by the horizontal surface on the crate. The friction force is positive if to the right, negative if to the left. Assume ??= 0.48, ??= 0.38.