Physics of Everyday Phenomena
9th Edition
ISBN: 9781260048469
Author: Griffith
Publisher: MCG
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Chapter 2, Problem 8CQ
The highway patrol sometimes uses radar guns to identify possible speeders and at other times uses associates in airplanes who note the time taken for a car to pass between two marks some distance apart on the highway. What does each of these methods measure, average speed or instantaneous speed? Can you think of situations in which either one of these methods might unfairly penalize a driver? Explain.
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Chapter 2 Solutions
Physics of Everyday Phenomena
Ch. 2 - Prob. 1CQCh. 2 - Suppose we choose inches as our basic unit of...Ch. 2 - What units would have an appropriate size for...Ch. 2 - A tortoise and a hare cover the same distance in a...Ch. 2 - A driver states that she was doing 80 when stopped...Ch. 2 - Does the speedometer on a car measure average...Ch. 2 - Is the average speed over several minutes more...Ch. 2 - The highway patrol sometimes uses radar guns to...Ch. 2 - Is the term vehicle density (as used in everyday...Ch. 2 - Prob. 10CQ
Ch. 2 - At the front end of a traffic jam, is the vehicle...Ch. 2 - A hockey puck is sliding on frictionless ice. It...Ch. 2 - A ball attached to a string is whirled in a...Ch. 2 - Prob. 14CQCh. 2 - A dropped ball gains speed as it falls. Can the...Ch. 2 - A driver of a car steps on the brakes, causing the...Ch. 2 - At a given instant in time, two cars are traveling...Ch. 2 - A car just starting up from a stop sign has zero...Ch. 2 - A car traveling with constant speed rounds a curve...Ch. 2 - A racing sports car traveling with a constant...Ch. 2 - In the graph shown here, velocity is plotted as a...Ch. 2 - A car moves along a straight line so that its...Ch. 2 - For the car whose distance is plotted against time...Ch. 2 - A car moves along a straight section of road so...Ch. 2 - For the car whose velocity is plotted in question...Ch. 2 - Look again at the velocity-versus-time graph for...Ch. 2 - Suppose the acceleration of a car increases with...Ch. 2 - When a car accelerates uniformly from rest, which...Ch. 2 - The velocity-versus-time graph of an object curves...Ch. 2 - For a uniformly accelerated car, is the average...Ch. 2 - A car traveling in the forward direction...Ch. 2 - A car starts from rest, accelerates uniformly for...Ch. 2 - Suppose that two runners run a 100-meter dash, but...Ch. 2 - Sketch a graph showing velocity-versus-time curves...Ch. 2 - A physics instructor walks with increasing speed...Ch. 2 - Prob. 36CQCh. 2 - Return to example box 2.4, but this time assume...Ch. 2 - A traveler covers a distance of 413 miles in a...Ch. 2 - A walker covers a distance of 2.4 km in a time of...Ch. 2 - Grass clippings are found to have an average...Ch. 2 - A driver drives for 2.5 hours at an average speed...Ch. 2 - A woman walks a distance of 504 m, with an average...Ch. 2 - A person in a hurry averages 70 MPH on a trip...Ch. 2 - A hiker walks with an average speed of 1.3 m/s....Ch. 2 - Prob. 8ECh. 2 - A car travels with an average speed of 65 MPH....Ch. 2 - Starting from rest and moving in a straight line,...Ch. 2 - Starting from rest, a car accelerates at a rate of...Ch. 2 - The velocity of a car decreases from 28 m/s to 20...Ch. 2 - A car traveling with an initial velocity of 16 m/s...Ch. 2 - A runner traveling with an initial velocity of 1.1...Ch. 2 - A car moving with an initial velocity of 32 m/s...Ch. 2 - A runner moving with an initial velocity of 4.0...Ch. 2 - If a world-class sprinter ran a distance of 100...Ch. 2 - Starting from rest, a car accelerates at a...Ch. 2 - A railroad engine moves forward along a straight...Ch. 2 - The velocity of a car increases with time, as...Ch. 2 - A car traveling due west on a straight road...Ch. 2 - A car traveling in a straight line with an initial...Ch. 2 - Just as car A is starting up, it is passed by car...
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