University Physics (14th Edition)
14th Edition
ISBN: 9780133969290
Author: Hugh D. Young, Roger A. Freedman
Publisher: PEARSON
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Textbook Question
Chapter 4, Problem 4.8E
You walk into an elevator, step onto a scale, and push the “up” button. You recall that your normal weight is 625 N. Draw a free-body diagram, (a) When the elevator has an upward acceleration of magnitude 2.50 m/s2, what does the scale read? (b) If you hold a 3.85-kg package by a light vertical string, what will be the tension in this string when the elevator accelerates as in part (a)?
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You walk into an elevator, step onto a scale, and push the “up” button. You recall that your normal weight is 625 N. Draw a free-body diagram. (a) When the elevator has an upward acceleration of magnitude 2.50 m/s2, what does the scale read? (b) If you hold a 3.85 kg package by a light vertical string, what will be the tension in this string when the elevator accelerates as in part (a)?
You walk into an elevator, step onto a scale, and push the “up” button. You also recall that your normal weight is 625 N. Start answering each of the following questions by drawing a free body diagram. (a) If the elevator has an acceleration of magnitude 2.5 m/s2 , what does the scale read? (b) If you start holding a 3.85-kg package by a light vertical string, what will be the tension in this string once the elevator begins accelerating?
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and the acceleration downward is of the same magnitude. (b) While accelerating downward, you
hold a small mass of 100 g attached to a string. What is the tension in the string? This elevator is in
the new BU Data Science building where g = 10 m/s². Your work should include free body
diagrams
Chapter 4 Solutions
University Physics (14th Edition)
Ch. 4 - Can a body be in equilibrium when only one force...Ch. 4 - A ball thrown straight up has zero velocity at its...Ch. 4 - A helium balloon hovers in midair, neither...Ch. 4 - When you fly in an airplane at night in smooth...Ch. 4 - If the two ends of a rope in equilibrium are...Ch. 4 - You tie a brick lo the end of a rope and whirl the...Ch. 4 - When a car stops suddenly, the passengers tend to...Ch. 4 - Some people say that the force of inertia (or...Ch. 4 - A passenger in a moving bus with no windows...Ch. 4 - Suppose you chose the fundamental physical...
Ch. 4 - Why is the earth only approximately an inertial...Ch. 4 - Does Newtons second law hold true for an observer...Ch. 4 - Some students refer to the quantity ma as the...Ch. 4 - The acceleration of a falling body is measured in...Ch. 4 - You can play catch with a softball in a bus moving...Ch. 4 - Students sometimes say that the force of gravity...Ch. 4 - Why can it hurt your foot more to kick a big rock...Ch. 4 - Its not the fall that hurts you; its the sudden...Ch. 4 - A person can dive into water from a height of 10 m...Ch. 4 - Why are cars designed to crumple in front and back...Ch. 4 - When a string barely strong enough lifts a heavy...Ch. 4 - A large crate is suspended from the end of a...Ch. 4 - Which feels a greater pull due to the earths...Ch. 4 - Why is it incorrect to say that 1.0 kg equals 2.2...Ch. 4 - A horse is hitched to a wagon. Since the wagon...Ch. 4 - True or false? You exert a push P on an object and...Ch. 4 - A large truck and a small compact car have a...Ch. 4 - When a car comes to a stop on a level highway,...Ch. 4 - A small compact car is pushing a large van that...Ch. 4 - Consider a tug-of-war between two people who pull...Ch. 4 - Boxes A and B are in contact on a horizontal,...Ch. 4 - A manual for student pilots contains this passage:...Ch. 4 - If your hands are wet and no towel is handy, you...Ch. 4 - If you squat down (such as when you examine the...Ch. 4 - When a car is hit from behind, the occupants may...Ch. 4 - In a head-on auto collision, passengers who are...Ch. 4 - In a head-on collision between a compact 1000-kg...Ch. 4 - Suppose you are in a rocket with no windows,...Ch. 4 - Two dogs pull horizontally on ropes attached to a...Ch. 4 - To extricate an SUV stuck in the mud, workmen use...Ch. 4 - BIO Jaw Injury. 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How...Ch. 4 - At the surface of Jupiters moon Io, the...Ch. 4 - A small car of mass 380 kg is pushing a large...Ch. 4 - BIO World-class sprinters can accelerate out of...Ch. 4 - The upward normal force exerted by the floor is...Ch. 4 - Boxes A and B are in contact on a horizontal,...Ch. 4 - A student of mass 45 kg jumps off a high diving...Ch. 4 - Section 4.6 Free-Body Diagrams 4.25Crates A and B...Ch. 4 - You pull horizontally on block B in Fig. F4.26,...Ch. 4 - A ball is hanging from a long siring that is tied...Ch. 4 - CP A .22-caliber rifle bullet traveling at 350 m/s...Ch. 4 - A chair of mass 12.0 kg is sitting on the...Ch. 4 - A large box containing your new computer sits on...Ch. 4 - CP A 5.60-kg bucket of water is accelerated upward...Ch. 4 - CP You have just landed on Planet X. You release a...Ch. 4 - Two adults and a child want to push a wheeled cart...Ch. 4 - CP An oil tankers engines have broken down, and...Ch. 4 - CP BIO A Standing Vertical Jump. 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