Physics for Scientists and Engineers, Technology Update (No access codes included)
9th Edition
ISBN: 9781305116399
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
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Chapter 12, Problem 12.18P
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, Technology Update (No access codes included)
Ch. 12 - Consider the object subject to the two forces of...Ch. 12 - Consider the object subject to the three forces in...Ch. 12 - A meterstick of uniform density is hung from a...Ch. 12 - For the three parts of this Quick Quiz, choose...Ch. 12 - The acceleration due to gravity becomes weaker by...Ch. 12 - A rod 7.0 in long is pivoted at a point 2.0 m from...Ch. 12 - Prob. 12.3OQCh. 12 - Two forces are acting on an object. Which of the...Ch. 12 - Prob. 12.5OQCh. 12 - A 20.0-kg horizontal plank 4.00 in long rests on...
Ch. 12 - Prob. 12.7OQCh. 12 - In analyzing the equilibrium of a flat, rigid...Ch. 12 - A certain wire, 3 m long, stretches by 1.2 mm when...Ch. 12 - The center of gravity of an ax is on the...Ch. 12 - A ladder stands on the ground, leaning against a...Ch. 12 - Prob. 12.2CQCh. 12 - (a) Give an example in which the net force acting...Ch. 12 - Prob. 12.4CQCh. 12 - Prob. 12.5CQCh. 12 - A girl has a large, docile dog she wishes to weigh...Ch. 12 - Prob. 12.7CQCh. 12 - What kind of deformation does a cube of Jell-O...Ch. 12 - What are the necessary conditions for equilibrium...Ch. 12 - Why is the following situation impossible? A...Ch. 12 - Prob. 12.3PCh. 12 - Prob. 12.4PCh. 12 - Your brother is opening a skateboard shop. He has...Ch. 12 - A circular pizza of radius R has a circular piece...Ch. 12 - Prob. 12.7PCh. 12 - Prob. 12.8PCh. 12 - Prob. 12.9PCh. 12 - Prob. 12.10PCh. 12 - A uniform beam of length 7.60 m and weight 4.50 ...Ch. 12 - A vaulter holds a 29.4-N pole in equilibrium by...Ch. 12 - A 15.0-in uniform ladder weighing 500 N rests...Ch. 12 - A uniform ladder of length L.and mass m1 rests...Ch. 12 - A flexible chain weighing 40.0 N hangs between two...Ch. 12 - A uniform beam of length L and mass m shown in...Ch. 12 - Figure P12.13 shows a claw hammer being used to...Ch. 12 - A 20.0-kg floodlight in a park is supported at the...Ch. 12 - Prob. 12.19PCh. 12 - Review. While Lost-a-Lot ponders his next move in...Ch. 12 - John is pushing his daughter Rachel in a...Ch. 12 - Prob. 12.22PCh. 12 - One end of a uniform 4.00-m-long rod of weight Fg...Ch. 12 - A 10.0-kg monkey climbs a uniform ladder with...Ch. 12 - A uniform plank of length 2.00 m and mass 30.0 kg...Ch. 12 - A steel wire of diameter 1 mm can support a...Ch. 12 - The deepest point in the ocean is in the Mariana...Ch. 12 - Assume Youngs modulus for bone is 1.50 1010 N/m2....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 - A 200-kg load is hung on a wire of length 4.00m,...Ch. 12 - A walkway suspended across a hotel lobby is...Ch. 12 - Review. A 2.00-m-long cylindrical steel wire with...Ch. 12 - Review. A 30.0-kg hammer, moving with speed 20.0...Ch. 12 - A bridge of length 50.0 m and mass 8.00 104 kg is...Ch. 12 - A uniform beam resting on two pivots has a length...Ch. 12 - Prob. 12.39APCh. 12 - The lintel of prestressed reinforced concrete in...Ch. 12 - Prob. 12.41APCh. 12 - When a person stands on tiptoe on one foot (a...Ch. 12 - A hungry bear weighing 700 N walks out on a beam...Ch. 12 - The following equations are obtained from a force...Ch. 12 - A uniform sign of weight Fg and width 2L hangs...Ch. 12 - A 1 200-N uniform boom at = 65 to the vertical is...Ch. 12 - Prob. 12.47APCh. 12 - Assume a person bends forward to lift a load with...Ch. 12 - A 10 000-N shark is supported by a rope attached...Ch. 12 - Why is the following situation impossible? A...Ch. 12 - A uniform beam of mass m is inclined at an angle ...Ch. 12 - Prob. 12.52APCh. 12 - When a circus performer performing on the rings...Ch. 12 - Figure P12.38 shows a light truss formed from...Ch. 12 - Prob. 12.55APCh. 12 - A stepladder of negligible weight is constructed...Ch. 12 - A stepladder of negligible weight is constructed...Ch. 12 - (a) Estimate the force with which a karate master...Ch. 12 - Two racquetballs, each having a mass of 170 g, are...Ch. 12 - Review. A wire of length L, Youngs modulus Y, and...Ch. 12 - Review. An aluminum wire is 0.850 m long and has a...Ch. 12 - Prob. 12.62APCh. 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 pole is propped between the floor and...Ch. 12 - In the What If? section of Example 12.2, let d...Ch. 12 - Figure P12.67 shows a vertical force applied...Ch. 12 - A uniform rod of weight Fg and length L is...
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