1. A uniform horizontal beam has a mass of 13.1 kg. As you see below, the cable makes an angle of 45 degrees with a vertical pole. The beam's right end is connected to the light (essentially mass-less) cable making a 45-degree angle with the beam. The beam's left end is hinged at pivot A on the rigid, fixed pole. The left end of the cable is also attached to the pole. See figure. Show all work. (a) (b) What is the tension T in the cable? What is the horizontal component of force FH exerted by pivot A on the beam? (c) What is the vertical component of force Fv exerted by pivot A on the beam ? (d) Assuming the beam length is 1.1 m, suppose a vandal severs the cable such that the tension becomes zero. Consider the moment just after the cable is cut and the beam is still in a horizontal position. At that instant, what is the magnitude of the torque (about pivot A) exerted by the gravitational force? What is the magnitude of the beam's angular acceleration about point A at this instant? POLE A CABLE 45

1. A uniform horizontal beam has a mass of 13.1 kg. As you see below, the cable makes an angle of 45 degrees with a vertical pole. The beam's right end is connected to the light (essentially mass-less) cable making a 45-degree angle with the beam. The beam's left end is hinged at pivot A on the rigid, fixed pole. The left end of the cable is also attached to the pole. See figure. Show all work. (a) (b) What is the tension T in the cable? What is the horizontal component of force FH exerted by pivot A on the beam? (c) What is the vertical component of force Fv exerted by pivot A on the beam ? (d) Assuming the beam length is 1.1 m, suppose a vandal severs the cable such that the tension becomes zero. Consider the moment just after the cable is cut and the beam is still in a horizontal position. At that instant, what is the magnitude of the torque (about pivot A) exerted by the gravitational force? What is the magnitude of the beam's angular acceleration about point A at this instant? POLE A CABLE 45

Physics for Scientists and Engineers

10th Edition

ISBN:9781337553278

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter12: Static Equilibrium And Elasticity

Section: Chapter Questions

Problem 10P: A 20.0-kg floodlight in a park is supported at the end of a horizontal beam of negligible mass that...

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