Physics for Scientists and Engineers with Modern Physics
4th Edition
ISBN: 9780131495081
Author: Douglas C. Giancoli
Publisher: Addison-Wesley
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Textbook Question
Chapter 12, Problem 72GP
A man doing push-ups pauses in the position shown in Fig. 12–86. His mass m = 68 kg. Determine the normal force exerted by the floor (a) on each band; (b) on each foot.
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Chapter 12 Solutions
Physics for Scientists and Engineers with Modern Physics
Ch. 12.1 - For simplicity, we wrote the equation in Example...Ch. 12.2 - We did not need to use the force equation to solve...Ch. 12.2 - CHAPTER-OPENING QUESTIONGuess Now! The diving...Ch. 12.2 - Why is it reasonable to ignore friction along the...Ch. 12.4 - Two steel wires have the same length and are under...Ch. 12 - Describe several situations in which an object is...Ch. 12 - A bungee jumper momentarily comes to rest at the...Ch. 12 - Prob. 3QCh. 12 - Your doctors scale has arms on which weights slide...Ch. 12 - A ground retaining wall is shown in Fig. 1240a....
Ch. 12 - Can the sum of the torques on an object be zero...Ch. 12 - A ladder, leaning against a wall, makes a 60 angle...Ch. 12 - A uniform meter stick supported at the 25-cm mark...Ch. 12 - Prob. 9QCh. 12 - Prob. 10QCh. 12 - Place yourself facing the edge of an open door....Ch. 12 - Prob. 12QCh. 12 - Prob. 13QCh. 12 - Which of the configurations of brick, (a) or (b)...Ch. 12 - Name the type of equilibrium for each position of...Ch. 12 - Is the Youngs modulus for a bungee cord smaller or...Ch. 12 - Examine how a pair of scissors or shears cuts...Ch. 12 - Materials such as ordinary concrete and stone are...Ch. 12 - (I) Three forces are applied to a tree sapling, as...Ch. 12 - (I) Approximately what magnitude force, FM, must...Ch. 12 - Prob. 3PCh. 12 - (I) A tower crane (Fig. 1248a) must always be...Ch. 12 - (II) Calculate the forces FA and FB that the...Ch. 12 - Prob. 6PCh. 12 - (II) The two trees in Fig. 1250 are 6.6 m apart. A...Ch. 12 - Prob. 8PCh. 12 - Prob. 9PCh. 12 - Prob. 10PCh. 12 - (II) Find the tension in the two cords shown in...Ch. 12 - (II) Find the tension in the two wires supporting...Ch. 12 - Prob. 13PCh. 12 - (II) The force required to pull the cork out of...Ch. 12 - (II) Calculate and FA and FB for the beam shown in...Ch. 12 - Prob. 16PCh. 12 - Prob. 17PCh. 12 - (II) Three children are trying to balance on a...Ch. 12 - (II) The Achilles tendon is attached to the rear...Ch. 12 - (II) A shop sign weighing 215 N is supported by a...Ch. 12 - (II) A traffic light hangs from a pole as shown in...Ch. 12 - (II) A uniform steel beam has a mass of 940 kg. On...Ch. 12 - (II) Two wires run from the top of a pole 2.6 m...Ch. 12 - (II) A large 62.0-kg board is propped at a 45...Ch. 12 - (II) Repeat Problem 24 assuming the coefficient of...Ch. 12 - (II) A 0.75-kg sheet hangs from a massless...Ch. 12 - (II) A uniform rod AB of length 5.0 m and mass M =...Ch. 12 - (III) A 56.0-kg person stands 2.0 m from the...Ch. 12 - (III) A door 2.30 m high and 1.30 m wide has a...Ch. 12 - (III) A cubic crate of side s = 2.0 m is...Ch. 12 - (III) A refrigerator is approximately a uniform...Ch. 12 - (III) A uniform ladder of mass m and length leans...Ch. 12 - Prob. 33PCh. 12 - (I) A nylon string on a tennis racket is under a...Ch. 12 - (I) A marble column of cross-sectional area 1.4 m2...Ch. 12 - (I) By how much is the column in Problem 35...Ch. 12 - (I) A sign (mass 1700 kg) hangs from the end of a...Ch. 12 - (II) How much pressure is needed to compress the...Ch. 12 - Prob. 39PCh. 12 - (II) At depths of 2000 m in the sea, the pressure...Ch. 12 - (III) A pole projects horizontally from the front...Ch. 12 - (I) The femur bone in the human leg has a minimum...Ch. 12 - (II) (a) What is the maximum tension possible in a...Ch. 12 - (II) If a compressive force of 3.3 104 N is...Ch. 12 - (II) (a) What is the minimum cross-sectional area...Ch. 12 - (II) Assume the supports of the uniform cantilever...Ch. 12 - (II) An iron bolt is used to connect two iron...Ch. 12 - (II) A steel cable is to support an elevator whose...Ch. 12 - (II) A heavy load Mg = 66.0 kN hangs at point E of...Ch. 12 - (II) Figure 1271 shows a simple truss that carries...Ch. 12 - (II) (a) What minimum cross-sectional area must...Ch. 12 - (II) onsider again Example 1211 but this time...Ch. 12 - (III) The truss shown in Fig. 1272 supports a...Ch. 12 - (III) Suppose in Example 1211, a 23-ton truck (m =...Ch. 12 - (III) For the Pratt truss shown in Fig. 1273,...Ch. 12 - (II) How high must a pointed arch be if it is to...Ch. 12 - The mobile in Fig. 1274 is in equilibrium. Object...Ch. 12 - A tightly stretched high wire is 36 m long. It...Ch. 12 - What minimum horizontal force F is needed to pull...Ch. 12 - A 28-kg round table is supported by three legs...Ch. 12 - When a wood shelf of mass 6.6 kg is fastened...Ch. 12 - Prob. 62GPCh. 12 - The center of gravity of a loaded truck depends on...Ch. 12 - In Fig. 1279, consider the right-hand...Ch. 12 - Assume that a single-span suspension bridge such...Ch. 12 - When a mass of 25 kg is hung from the middle of a...Ch. 12 - The forces acting on a 77,000-kg aircraft flying...Ch. 12 - A uniform flexible steel cable of weight mg is...Ch. 12 - A 20.0-m-long uniform beam weighing 650 N rests on...Ch. 12 - A cube of side l rests on a rough floor. It is...Ch. 12 - A 65.0-kg painter is on a uniform 25-kg scaffold...Ch. 12 - A man doing push-ups pauses in the position shown...Ch. 12 - A 23-kg sphere rests between two smooth planes as...Ch. 12 - A 15.0-kg ball is supported from the ceiling by...Ch. 12 - Parachutists whose chutes have failed to open have...Ch. 12 - A steel wire 2.3 mm in diameter stretches by...Ch. 12 - A 2500-kg trailer is attached to a stationary...Ch. 12 - Prob. 78GPCh. 12 - A 25-kg object is being lifted by pulling on the...Ch. 12 - A uniform 6.0-m-long ladder of mass 16.0 kg leans...Ch. 12 - There is a maximum height of a uniform vertical...Ch. 12 - A 95,000-kg train locomotive starts across a...Ch. 12 - A 23.0-kg backpack is suspended midway between two...Ch. 12 - A uniform beam of mass M and length l is mounted...Ch. 12 - Two identical, uniform beams are symmetrically set...Ch. 12 - If 35 kg is the maximum mass m that a person can...Ch. 12 - (a) Estimate the magnitude of the force FM the...Ch. 12 - One rod of the square frame shown in Fig. 1295...Ch. 12 - A steel rod of radius R = 15 cm and length 0,...Ch. 12 - A home mechanic wants to raise the 280-kg engine...Ch. 12 - A 2.0-m-high box with a 1.0-m-squarc base is moved...Ch. 12 - You are on a pirate ship and being forced to walk...Ch. 12 - A uniform sphere of weight mg and radius r0 is...Ch. 12 - Use the method of joints to determine the force in...Ch. 12 - A uniform ladder of mass m and length leans at an...Ch. 12 - In a mountain-climbing technique called the...Ch. 12 - (III) A metal cylinder has an original diameter of...Ch. 12 - (III) Two springs, attached by a rope, are...
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