College Physics: A Strategic Approach (4th Edition)
4th Edition
ISBN: 9780134609034
Author: Randall D. Knight (Professor Emeritus), Brian Jones, Stuart Field
Publisher: PEARSON
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Textbook Question
Chapter 14, Problem 19CQ
Sprinters push off from the ball of their foot, then bend their knee to bring their foot up close to the body as they swing their leg forward for the next stride. Why is this an effective strategy for running fast?
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14-4.12. A flexible rope, 80 ft long and weighing 0.5 lb/ft, passes over
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Figure P-14-4.12
Sprinters push off from the ball of their foot, then bend their knee to bring their foot up close to the body as they swing their leg forward for the next stride. Why is this an effective strategy for running fast?
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Chapter 14 Solutions
College Physics: A Strategic Approach (4th Edition)
Ch. 14 - Prob. 1CQCh. 14 - A persons heart rate is given in beats per minute....Ch. 14 - Figure Q14.3 shows the position-versus-time graph...Ch. 14 - A tall building is swaying back and forth on a...Ch. 14 - A child is on a swing, gently swinging back and...Ch. 14 - A block oscillating on a spring has an amplitude...Ch. 14 - A block oscillating on a spring has a maximum...Ch. 14 - Prob. 8CQCh. 14 - For the graph in Figure Q14.9, determine the...Ch. 14 - For the graph in Figure Q14.10 , determine the...
Ch. 14 - A block oscillating on a spring has period t = 2.0...Ch. 14 - Prob. 12CQCh. 14 - Flies flap their wings at frequencies much too...Ch. 14 - Denver is at a higher elevation than Miami; the...Ch. 14 - If you want to play a tune on wine glasses, youll...Ch. 14 - Prob. 16CQCh. 14 - Prob. 17CQCh. 14 - Gibbons move through the trees by swinging from...Ch. 14 - Sprinters push off from the ball of their foot,...Ch. 14 - Humans have a range of hearing of approximately 20...Ch. 14 - Prob. 21CQCh. 14 - Weve seen that stout tendons in the legs of...Ch. 14 - A spring has an unstretched length of 20 cm. A 100...Ch. 14 - Figure Q14.24 represents the motion of a mass on a...Ch. 14 - A ball of mass m oscillates on a spring with...Ch. 14 - Prob. 26MCQCh. 14 - Prob. 27MCQCh. 14 - A heavy brass ball is used to make a pendulum with...Ch. 14 - Very loud sounds can damage hearing by injuring...Ch. 14 - When a guitar string plays the note A, the string...Ch. 14 - In the aftermath of an intense earthquake, the...Ch. 14 - In taking your pulse, you count 75 heartbeats in 1...Ch. 14 - A spring scale hung from the ceiling stretches by...Ch. 14 - A heavy steel ball is hung from a cord to make a...Ch. 14 - An air-track glider attached to a spring...Ch. 14 - An air-track glider is attached to a spring. The...Ch. 14 - What are the (a) amplitude and (b) frequency of...Ch. 14 - What are the (a) amplitude and (b) frequency of...Ch. 14 - Prob. 10PCh. 14 - Prob. 11PCh. 14 - Prob. 12PCh. 14 - Some passengers on an ocean cruise may suffer from...Ch. 14 - The New England Merchants Bank Building in Boston...Ch. 14 - Prob. 15PCh. 14 - Prob. 16PCh. 14 - We can model the motion of a bumblebees wing as...Ch. 14 - Prob. 18PCh. 14 - a. When the displacement of a mass on a spring is...Ch. 14 - A 1.0 kg block is attached to a spring with spring...Ch. 14 - A block attached to a spring with unknown spring...Ch. 14 - A 200 g air-track glider is attached to a spring....Ch. 14 - The position of a 50 g oscillating mass is given...Ch. 14 - A 50-em-long spring is suspended from the ceiling....Ch. 14 - A 200 g mass attached to a horizontal spring...Ch. 14 - A 507 g mass oscillates with an amplitude of 10.0...Ch. 14 - A mass on a string of unknown length oscillates as...Ch. 14 - The mass in a pendulum clock completes one...Ch. 14 - A 200 g ball is tied to a string. It is pulled to...Ch. 14 - The free-fall acceleration on the moon is 1.62...Ch. 14 - Astronauts on the first trip to Mars take along a...Ch. 14 - A building is being knocked down with a wrecking...Ch. 14 - Interestingly, there have been several studies...Ch. 14 - Prob. 34PCh. 14 - You and your friends find a rope that hangs down...Ch. 14 - Prob. 37PCh. 14 - Prob. 38PCh. 14 - The amplitude of an oscillator decreases to 36.8%...Ch. 14 - A physics department has a Foucault pendulum, a...Ch. 14 - Calculate and draw an accurate displacement graph...Ch. 14 - A small earthquake starts a lamppost vibrating...Ch. 14 - Prob. 43PCh. 14 - Prob. 44PCh. 14 - Prob. 45PCh. 14 - Taipei 101 (a 101-story building in Taiwan) is...Ch. 14 - A 25 kg child sits on a 2.0-m-long rope swing. You...Ch. 14 - Prob. 48PCh. 14 - Vision is blurred if the head is vibrated at 29 Hz...Ch. 14 - A spring has an unstretched length of 12 cm. When...Ch. 14 - A 0.40 kg ball is suspended from a spring with...Ch. 14 - Prob. 52GPCh. 14 - A spring with spring constant 15.0 N/m hangs from...Ch. 14 - Prob. 54GPCh. 14 - Prob. 55GPCh. 14 - A spring is hung from the ceiling. When a coffee...Ch. 14 - On your first trip to Planet X you happen to take...Ch. 14 - Prob. 58GPCh. 14 - Prob. 59GPCh. 14 - As weve seen, astronauts measure their mass by...Ch. 14 - A 100 g ball attached to a spring with spring...Ch. 14 - The ultrasonic transducer used in a medical...Ch. 14 - A compact car has a mass of 1200 kg. When empty,...Ch. 14 - A car with a total mass of 1400 kg (including...Ch. 14 - A 500 g air-track glider attached to a spring with...Ch. 14 - Prob. 67GPCh. 14 - Prob. 68GPCh. 14 - Prob. 70GPCh. 14 - Prob. 71GPCh. 14 - Orangutans can move by brachiation, swinging like...Ch. 14 - An infants toy has a 120 g wooden animal hanging...Ch. 14 - Prob. 74GPCh. 14 - A 200 g oscillator in a vacuum chamber has a...Ch. 14 - Prob. 76GPCh. 14 - We can make a static measurement to deduce the...Ch. 14 - If, during a stride, the stretch causes her center...Ch. 14 - If we imagine a full cycle of the oscillation,...Ch. 14 - Given what you have calculated for the period of...Ch. 14 - Suppose a 12 mg fly lands in the center of a...Ch. 14 - Modeling the motion of the fly on the web as a...Ch. 14 - If the web were vertical rather than horizontal,...Ch. 14 - Spiders are more sensitive to oscillations at...
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