Essential University Physics (3rd Edition)
3rd Edition
ISBN: 9780134202709
Author: Richard Wolfson
Publisher: PEARSON
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Textbook Question
Chapter 4, Problem 60P
Your engineering firm is asked to specify the maximum load for the elevators in a new building. Each elevator has mass 490 kg when empty and maximum acceleration 2.24 m/s2. The elevator cables can withstand a maximum tension of 19.5 kN before breaking. For safety, you need to ensure that the tension never exceeds two-thirds of that value. What do you specify for the maximum load? How many 70-kg people is that?
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Chapter 4 Solutions
Essential University Physics (3rd Edition)
Ch. 4.2 - A curved barrier lies on a horizontal tabletop, as...Ch. 4.2 - A nonzero net force acts on an object. Which of...Ch. 4.4 - A popular childrens book explains the...Ch. 4.5 - For each of the following situations, would the...Ch. 4.6 - The figure shows two blocks with two forces acting...Ch. 4.6 - (1) Would the answer to (a) in Example 4.5 change...Ch. 4 - Distinguish the Aristotelian and Galilean/New...Ch. 4 - A ball bounces off a wall with the same speed it...Ch. 4 - We often use the term inertia to describe human...Ch. 4 - Does a body necessarily move in the direction of...
Ch. 4 - A truck crashes into a stalled car. A student...Ch. 4 - A barefoot astronaut kicks a ball, hard, across a...Ch. 4 - The surface gravity on Jupiters moon Io is...Ch. 4 - In paddling a canoe, you push water backward with...Ch. 4 - Is it possible for a nonzero net force to act on...Ch. 4 - As your plane accelerates down the runway, you...Ch. 4 - A driver tells passengers to buckle their...Ch. 4 - If you cut a spring in half, is the spring...Ch. 4 - As youre sitting on a chair, theres a...Ch. 4 - Section 4.2 Newtons First and Second Laws A subway...Ch. 4 - A 61-Mg railroad locomotive can exert a 0.12-MN...Ch. 4 - A small plane accelerates down the runway at 7.2...Ch. 4 - A car leaves the road traveling at 110 km/h and...Ch. 4 - By how much does the force required to stop a car...Ch. 4 - Kinesin is a motor protein responsible for moving...Ch. 4 - Starting from rest and undergoing constant...Ch. 4 - In an egg-dropping contest, a student encases an...Ch. 4 - In a front-end collision, a 1300-kg car with...Ch. 4 - Show that the units of acceleration can be written...Ch. 4 - Your spaceship crashes on one of the Suns planets....Ch. 4 - Your friend can barely lift a 35-kg concrete block...Ch. 4 - A cereal box says net weight 340 grams. Whats the...Ch. 4 - Youre a safely engineer for a bridge spanning the...Ch. 4 - The gravitational acceleration at the...Ch. 4 - A 50-kg parachutist descends at a steady 40 km/h....Ch. 4 - A 930-kg motorboat accelerates away from a dock at...Ch. 4 - An elevator accelerates downward at 2.4 m/s2. What...Ch. 4 - At 560 metric tons, the Airbus A-380 is the worlds...Ch. 4 - Youre an engineer working on Ares I, NASAs...Ch. 4 - You slop into an elevator, and it accelerates to a...Ch. 4 - What upward gravitational force does a 5600-kg...Ch. 4 - Your friends mass is 65 kg. If she jumps off a...Ch. 4 - What force is necessary to stretch a spring 48 cm,...Ch. 4 - A 35-N force is applied to a spring with spring...Ch. 4 - A spring with spring constant k = 340 N/m is used...Ch. 4 - A 1.25-kg object is moving in the x-direction at...Ch. 4 - An airplane encounters sudden turbulence, and you...Ch. 4 - A 74-kg tree surgeon rides a cherry picker lift to...Ch. 4 - A dancer executes a vertical jump during which the...Ch. 4 - Find expressions for the force needed to bring an...Ch. 4 - An elevator moves upward at 5.2 m/s. Whats its...Ch. 4 - A 2.50-kg object is moving along the x-axis at...Ch. 4 - Blocks of 1.0, 2.0, and 3.0 kg are lined up on a...Ch. 4 - A child pulls an 11-kg wagon with a horizontal...Ch. 4 - Biophysicists use an arrangement of laser beams...Ch. 4 - A force F is applied to a spring of spring...Ch. 4 - A 22(M)-kg airplane pulls two gliders, the first...Ch. 4 - A biologist is studying the growth of rats on the...Ch. 4 - An elastic towrope has spring constant 1300 N/m....Ch. 4 - A 2.0-kg mass and a 3.0-kg mass are on a...Ch. 4 - Youre an automotive engineer designing the crumple...Ch. 4 - Frogs tongues dart out to catch insects, with...Ch. 4 - Two large crates, with masses 640 kg and 490 kg,...Ch. 4 - What force do the blades of a 4300-kg helicopter...Ch. 4 - What engine thrust (force) is needed to accelerate...Ch. 4 - Your engineering firm is asked to specify the...Ch. 4 - With its fuel tanks half full, an F-35A jet...Ch. 4 - Two springs have the same unstretched length but...Ch. 4 - Although we usually write Newtons second law for...Ch. 4 - A railroad car is being pulled beneath a grain...Ch. 4 - A block 20% more massive than you hangs from a...Ch. 4 - Youre asked to calibrate a device used to measure...Ch. 4 - A spider of mass ms drapes a silk thread of...Ch. 4 - Figure 4.27 shows vertical accelerometer data from...Ch. 4 - A hockey stick is in contact with a 165-g puck for...Ch. 4 - After parachuting through the Martian atmosphere,...Ch. 4 - Your airplane is caught in a brief, violent...Ch. 4 - Youre assessing the Engineered Material Arresting...Ch. 4 - Two masses are joined by a massless string. A 30-N...Ch. 4 - A mass M hangs from a uniform rope of length L and...Ch. 4 - Jerk is the rate of change of acceleration, and...Ch. 4 - Laptop computers are equipped with accelerometers...Ch. 4 - Laptop computers are equipped with accelerometers...Ch. 4 - Laptop computers are equipped with accelerometers...Ch. 4 - Laptop computers are equipped with accelerometers...
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