FUNDAMENTALS OF PHYSICS
12th Edition
ISBN: 9781119798606
Author: Halliday
Publisher: WILEY
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Chapter 7, Problem 17P
SSM WWW A helicopter lifts a 72 kg astronaut 15 m vertically from the ocean by means of a cable. The acceleration of the astronaut is g/10. How much work is done on the astronaut by (a) the force from the helicopter and (b) the gravitational force on her? Just before she reaches the helicopter, what are her (c) kinetic energy and (d) speed?
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Chapter 7 Solutions
FUNDAMENTALS OF PHYSICS
Ch. 7 - Prob. 1QCh. 7 - Figure 7-16a shows two horizontal forces that act...Ch. 7 - Is positive or negative work done by a constant...Ch. 7 - Spring A is stiffer than spring B kA kB. The...Ch. 7 - In three situations, a single force acts on a...Ch. 7 - Figure 7-23 shows three arrangements of a block...Ch. 7 - SSM A proton mass m = 1.67 1027 kg is being...Ch. 7 - If a Saturn V rocket with an Apollo spacecraft...Ch. 7 - On August 10, 1972, a large meteorite skipped...Ch. 7 - An explosion at ground level leaves a crater with...
Ch. 7 - A father racing his son has half the kinetic...Ch. 7 - A ice block floating in a river is pushed through...Ch. 7 - The only force acting on a 2.0 kg canister that is...Ch. 7 - A coin slides over a frictionless plane and across...Ch. 7 - A 12.0 N force with a fixed orientation does work...Ch. 7 - A luge and its rider, with a total mass of 85 kg,...Ch. 7 - SSM WWW A helicopter lifts a 72 kg astronaut 15 m...Ch. 7 - a In 1975 the roof of Montreals Velodrome, witha...Ch. 7 - 21 SSM A cord is used to vertically lower an...Ch. 7 - A cave rescue team lifts an injured spelunker...Ch. 7 - In Fig. 7-10, we must apply a force of magnitude...Ch. 7 - During spring semester at MIT, residents of the...Ch. 7 - In Fig. 7-10a, a block of mass m lies on a...Ch. 7 - SSM WWW The only force acting on a 2.0 kg body as...Ch. 7 - SSM WWW The force on a particle is directed along...Ch. 7 - A 1.5 kg block is initially at rest on a...Ch. 7 - GO A force F= cx3.00x2iacts on a particle as the...Ch. 7 - A can of sardines is made to move along an xaxis...Ch. 7 - A single force acts on a 3.0 kg particle-like...Ch. 7 - GO Figure 7-41 shows a cord attached to a cart...Ch. 7 - SSM A force of 5.0 N acts on a 15 kg body...Ch. 7 - A skier is pulled by a towrope up a frictionless...Ch. 7 - SSM ILW A 100 kg block is pulled at a constant...Ch. 7 - The loaded cab of an elevator has a mass of 3.0 ...Ch. 7 - A machine carries a 4.0 kg package from an initial...Ch. 7 - A 0.30 kg ladle sliding on a horizontal...Ch. 7 - Prob. 49PCh. 7 - a At a certain instant, a particle-like object is...Ch. 7 - A force F= 3.00 N i 7.00 N j 7.00 N k acts on...Ch. 7 - A funny car accelerates from rest through a...Ch. 7 - SSM A horse pulls a cart with a force of 40 lb at...Ch. 7 - An initially stationary 2.0 kg object accelerates...Ch. 7 - To pull a 50 kg crate across a horizontal...Ch. 7 - A frightened child is restrained by her mother as...Ch. 7 - How much work is done by a force F= 2x N i 3 N j,...Ch. 7 - 63 SSM To push a 25.0 kg crate up a frictionless...Ch. 7 - Boxes are transported from one location to another...Ch. 7 - If a car of mass 1200 kg is moving along a highway...Ch. 7 - An iceboat is at rest on a frictionless frozen...Ch. 7 - If a ski lift raises 100 passengers averaging 660...Ch. 7 - A force F= 4.0 N i cj acts on a particle as the...Ch. 7 - Prob. 71PCh. 7 - Prob. 72PCh. 7 - Prob. 73PCh. 7 - Prob. 74PCh. 7 - Prob. 75PCh. 7 - Prob. 76PCh. 7 - Prob. 77PCh. 7 - Prob. 78P
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