Physics: Principles with Applications
7th Edition
ISBN: 9780321625922
Author: Douglas C. Giancoli
Publisher: Addison-Wesley
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Textbook Question
Chapter 9, Problem 13Q
Why is it more difficult to do sit-ups when your knees are bent than when your legs are stretched out?
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Chapter 9 Solutions
Physics: Principles with Applications
Ch. 9 - Prob. 1OQCh. 9 - Describe several situations in which an object is...Ch. 9 - Prob. 2QCh. 9 - You can find the center of gravity of a meter...Ch. 9 - Prob. 4QCh. 9 - A ground retaining wall is shown in Fig. 9-36a...Ch. 9 - Can the sum of the torques on an object be zero...Ch. 9 - A ladder, leaning against a wall, makes a 60°...Ch. 9 - A uniform meter stick supported at the 25-cm mark...Ch. 9 - Why do you tend to lean backward when carrying a...
Ch. 9 - Figure 9-38 shows a cone. Explain how to lay it on...Ch. 9 - Prob. 11QCh. 9 - Why is it not possible to sit upright in a chair...Ch. 9 - Why is it more difficult to do sit-ups when your...Ch. 9 - Explain why touching your toes while you are...Ch. 9 - Prob. 15QCh. 9 - Name the type of equilibrium for each position of...Ch. 9 - (
17.
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Is the Young's modulus for a bungee cord...Ch. 9 - Prob. 18QCh. 9 - Prob. 19QCh. 9 - A 60-kg woman stands on the very end of a uniform...Ch. 9 - Prob. 2MCQCh. 9 - Prob. 3MCQCh. 9 - Prob. 4MCQCh. 9 - Two children are balanced on opposite sides of a...Ch. 9 - Prob. 6MCQCh. 9 - Prob. 7MCQCh. 9 - Prob. 8MCQCh. 9 - Prob. 9MCQCh. 9 - Prob. 10MCQCh. 9 - Three forces are applied to a tree sapling, as...Ch. 9 - Prob. 2PCh. 9 - 3(I) A tower crane ( Fig. 9-48a) must always be...Ch. 9 - What is the mass of the diver in Fig. 9-49 if she...Ch. 9 - Prob. 5PCh. 9 - Figure 9-50 shows a pair of forceps used to hold a...Ch. 9 - Prob. 7PCh. 9 - The two trees in Fig. 9-51 are 6.6 m apart. A...Ch. 9 - Prob. 9PCh. 9 - Prob. 10PCh. 9 - Prob. 11PCh. 9 - Find the tension in the two cords shown in Fig....Ch. 9 - Prob. 13PCh. 9 - Prob. 14PCh. 9 - The force required to pull the cork out of the top...Ch. 9 - Prob. 16PCh. 9 - Three children are trying to balance on a seesaw,...Ch. 9 - A shop sign weighing 215 N hangs from the end of a...Ch. 9 - Prob. 19PCh. 9 - Prob. 20PCh. 9 - Prob. 21PCh. 9 - 22 (II) A 20.0-m-long uniform beam weighing 650 N...Ch. 9 - Prob. 23PCh. 9 - Prob. 24PCh. 9 - Prob. 25PCh. 9 - Prob. 26PCh. 9 - A uniform rod AB of length 5.0 m and mass M=3.S kg...Ch. 9 - You are on a pirate ship and being forced to walk...Ch. 9 - Prob. 29PCh. 9 - Prob. 30PCh. 9 - Prob. 31PCh. 9 - Prob. 32PCh. 9 - Prob. 33PCh. 9 - Prob. 34PCh. 9 - Prob. 35PCh. 9 - 36 (II) The Achilles tendon is attached to the...Ch. 9 - If 25 kg is the maximum mass m that a person can...Ch. 9 - Prob. 38PCh. 9 - Prob. 39PCh. 9 - Prob. 40PCh. 9 - A marble column of cross-sectional area 1.4 m2...Ch. 9 - Prob. 42PCh. 9 - A sign (mass 1700 kg) hangs from the bottom end of...Ch. 9 - Prob. 44PCh. 9 - Prob. 45PCh. 9 - Prob. 46PCh. 9 - A steel wire 2.3 mm in diameter stretches by...Ch. 9 - Prob. 48PCh. 9 - Prob. 49PCh. 9 - Prob. 50PCh. 9 - Prob. 51PCh. 9 - Prob. 52PCh. 9 - (a) What is the minimum cross-sectional area...Ch. 9 - Prob. 54PCh. 9 - Prob. 55PCh. 9 - Prob. 56PCh. 9 - Prob. 57PCh. 9 - Prob. 58GPCh. 9 - Prob. 59GPCh. 9 - Prob. 60GPCh. 9 - Prob. 61GPCh. 9 - Prob. 62GPCh. 9 - Prob. 63GPCh. 9 - Prob. 64GPCh. 9 - When a mass of 25 kg is hung from the middle of a...Ch. 9 - Prob. 66GPCh. 9 - Prob. 67GPCh. 9 - Prob. 68GPCh. 9 - Prob. 69GPCh. 9 - Prob. 70GPCh. 9 - Prob. 71GPCh. 9 - Prob. 72GPCh. 9 - Prob. 73GPCh. 9 - A 2.0-m-high box with a 1.0-m-square base is moved...Ch. 9 - Prob. 75GPCh. 9 - Prob. 76GPCh. 9 - Prob. 77GPCh. 9 - Prob. 78GPCh. 9 - In a mountain-climbing technique called the...Ch. 9 - Prob. 80GPCh. 9 - A cubic crate of side s=20m is top-heavy: its cgis...
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- Is it possible to rest a ladder against a rough wall when the floor is frictionless?arrow_forwardA cook holds a 2.00-kg carton of milk at arm's length P8.19). What force FB must be exerted by the biceps muscle? (Ignore the weight of the forearm.) Figure P8.19arrow_forwardStand straight and comfortably with your feet about shoulderswidth apart. Now lift one of your legs so that you are balanced ononly one foot. Notice how your body moves. Explain why it moves.arrow_forward
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