Physics for Scientists and Engineers
10th Edition
ISBN: 9781337553278
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
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Chapter 12, Problem 10P
A 20.0-kg floodlight in a park is supported at the end of a horizontal beam of negligible mass that is hinged to a pole as shown in Figure P12.10. A cable at an angle of θ = 30.0° with the beam helps support the light. (a) Draw a force diagram for the beam. By computing torques about an axis at the hinge at the left-hand end of the beam, find (b) the tension in the cable, (c) the horizontal component of the force exerted by the pole on the beam, and (d) the vertical component of this force. Now solve the same problem from the force diagram from part (a) by computing torques around the junction between the cable and the beam at the right-hand end of the beam. Find (e) the vertical component of the force exerted by the pole on the beam, (f) the tension in the cable, and (g) the horizontal component of the force exerted by the pole on the beam. (h) Compare the solution to parts (b) through (d) with the solution to parts (c) through (g). Is either solution more accurate?
Figure P12.10
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Chapter 12 Solutions
Physics for Scientists and Engineers
Ch. 12.1 - Consider the object subject to the two forces of...Ch. 12.1 - Consider the object subject to the three forces in...Ch. 12.2 - A meterstick of uniform density is hung from a...Ch. 12.4 - For the three parts of this Quick Quiz, choose...Ch. 12 - You are building additional storage space in your...Ch. 12 - Why is the following situation impossible? A...Ch. 12 - Prob. 3PCh. 12 - A circular pizza of radius R has a circular piece...Ch. 12 - Your brother is opening a skateboard shop. He has...Ch. 12 - A uniform beam of length 7.60 m and weight 4.50 ...
Ch. 12 - Prob. 7PCh. 12 - A uniform beam of length L and mass m shown in...Ch. 12 - A flexible chain weighing 40.0 N hangs between two...Ch. 12 - A 20.0-kg floodlight in a park is supported at the...Ch. 12 - Prob. 11PCh. 12 - Review. While Lost-a-Lot ponders his next move in...Ch. 12 - Figure P12.13 shows a claw hammer being used to...Ch. 12 - A 10.0-kg monkey climbs a uniform ladder with...Ch. 12 - John is pushing his daughter Rachel in a...Ch. 12 - Prob. 16PCh. 12 - The deepest point in the ocean is in the Mariana...Ch. 12 - A steel wire of diameter 1 mm can support a...Ch. 12 - A child slides across a floor in a pair of...Ch. 12 - Evaluate Youngs modulus for the material whose...Ch. 12 - Assume if the shear stress in steel exceeds about...Ch. 12 - When water freezes, it expands by about 9.00%....Ch. 12 - Review. A 30.0-kg hammer, moving with speed 20.0...Ch. 12 - A uniform beam resting on two pivots has a length...Ch. 12 - A bridge of length 50.0 m and mass 8.00 104 kg is...Ch. 12 - Prob. 26APCh. 12 - The lintel of prestressed reinforced concrete in...Ch. 12 - The following equations are obtained from a force...Ch. 12 - A hungry bear weighing 700 N walks out on a beam...Ch. 12 - A 1 200-N uniform boom at = 65 to the vertical is...Ch. 12 - A uniform sign of weight Fg and width 2L hangs...Ch. 12 - When a person stands on tiptoe on one foot (a...Ch. 12 - A 10 000-N shark is supported by a rope attached...Ch. 12 - Assume a person bends forward to lift a load with...Ch. 12 - A uniform beam of mass m is inclined at an angle ...Ch. 12 - Why is the following situation impossible? A...Ch. 12 - When a circus performer performing on the rings...Ch. 12 - Figure P12.38 shows a light truss formed from...Ch. 12 - Prob. 39APCh. 12 - A stepladder of negligible weight is constructed...Ch. 12 - A stepladder of negligible weight is constructed...Ch. 12 - Review. A wire of length L, Youngs modulus Y, and...Ch. 12 - Two racquetballs, each having a mass of 170 g, are...Ch. 12 - Prob. 44APCh. 12 - Review. An aluminum wire is 0.850 m long and has a...Ch. 12 - You have been hired as an expert witness in a case...Ch. 12 - A 500-N uniform rectangular sign 4.00 m wide and...Ch. 12 - A steel cable 3.00 cm2 in cross-sectional area has...Ch. 12 - A uniform rod of weight Fg and length L is...Ch. 12 - In the What If? section of Example 12.2, let d...
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