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 4, Problem 26P
(III) A person jumps from the roof of a house 3.9-m high. When he strikes the ground below, he bends his knees so that his torso decelerates over an approximate distance of 0.70 m. If the mass of his torso (excluding legs) is 42 kg. find (a) his velocity just before his feet strike the ground, and (b) the average force exerted on his torso by his legs during deceleration.
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Chapter 4 Solutions
Physics for Scientists and Engineers with Modern Physics
Ch. 4.4 - Suppose you watch a cup slide on the (smooth)...Ch. 4.5 - Return to the first Chapter-Opening Question, page...Ch. 4.5 - A massive truck collides head-on with a small...Ch. 4.5 - If you push on a heavy desk, does it always push...Ch. 4.7 - A 10.0-kg box is dragged on a horizontal...Ch. 4 - Why does a child in a wagon seem to fall backward...Ch. 4 - A box rests on the (frictionless) bed of a truck....Ch. 4 - If the acceleration of an object is zero, are no...Ch. 4 - If an object is moving, is it possible for the net...Ch. 4 - Only one force acts on an object. Can the object...
Ch. 4 - When a golf ball is dropped to the pavement, it...Ch. 4 - If you walk along a log floating on a lake, why...Ch. 4 - Why might your foot hurt if you kick a heavy desk...Ch. 4 - When you are running and want to slop quickly, you...Ch. 4 - (a) Why do you push down harder on the pedals of a...Ch. 4 - A father and his young daughter are ice skating....Ch. 4 - Suppose that you are standing on a cardboard...Ch. 4 - A stone hangs by a fine thread from the ceiling,...Ch. 4 - The force of gravity on a 2-kg rock is twice as...Ch. 4 - Would a spring scale carried to the Moon give...Ch. 4 - You pull a box with a constant force across a...Ch. 4 - When an object falls freely under the influence of...Ch. 4 - Compare the effort (or force) needed to lift a...Ch. 4 - Which of the following objects weighs about 1 N:...Ch. 4 - According to Newtons third law. each team in a tug...Ch. 4 - When you stand still on the ground, how large a...Ch. 4 - Whiplash sometimes results from an automobile...Ch. 4 - Mary exerts an upward force of 40N to hold a bag...Ch. 4 - A bear sling, Fig. 430, in used in some national...Ch. 4 - (I) What force is needed to accelerate a child on...Ch. 4 - (1) A net force of 265N accelerates a bike and...Ch. 4 - (I) What is the weight of a 68-kg astronaut (a) on...Ch. 4 - (I) How much tension must a rope withstand if it...Ch. 4 - (II) Superman must stop a 120-km/h train in 150 m...Ch. 4 - (II) What average force is required to stop a...Ch. 4 - (II) Estimate the average force exerted by a...Ch. 4 - (II) A 0.140-kg baseball traveling 35.0 m/s...Ch. 4 - (II) A fisherman yanks a fish vertically out of...Ch. 4 - (II) A 20.0-kg box rests on a table. 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