The trooper, traveling about twice as fast as the car, must swerve (ijai) EXERCISE : Suppose the driver in this example now slams on the brakes, stopping the car in 4 s. Find (a) the acceleration, (b) the distance the car travels while braking, assuming the acceleration is constant, and (c) the average velocity. ANSWERS (a) -4.38 m/s (b) 35.0 m (c) 8.75 m/s Example-2: GOAL Solve a problem involving two objects, one moving at con- stant acceleration and the other at constant velocity. a = -1.00 s ta = 0 PROBLEM A car traveling at a constant speed of 24.0 m/s passes a trooper hidden behind a billboard, as in next figure. One second after the speeding car passes the billboard, the trooper sets off in chase with a constant acceleration of 3.00 m/s. (a) How long does it take the trooper to overtake the speeding car? (b) How fast is the trooper going at that time? SOLUTION (a) How long does it take the trooper to overtake the car? Write the equation for the car's displacement: , Axar = Xar = tht + ař Take x, = 24.0 m, v, = 24.0 m/s, and acar 0. Solve + vt = 24.0 m + (24.0 m/s)t Xar= Nrite the equation for the trooper's position, taking - 0, v,= 0, and aer = 3.00 m/s: Kurooper = 4r0oper = }(3.00 m/s*) = (1.50 m/s³) Set oper=r and solve the quadratic equation. (The quadratic formula appears in Appendix A, Equation A.8.) Only the positive root is meaningful. 14 %3D (1.50 m/s)t 24.0 m + (24.0 m/s)t (1.50 m/s)12- (24.0 m/s)t- 24.0 m 0 1= 16.9 s (b) Find the trooper's speed at that time. Substitute the time into the trooper's velocity cquation: = v, + arooper = 50.7 m/s Vrooper =0 + (3.00 m/s®)(16.9 s) X voli REMARKS: equal ne and
The trooper, traveling about twice as fast as the car, must swerve (ijai) EXERCISE : Suppose the driver in this example now slams on the brakes, stopping the car in 4 s. Find (a) the acceleration, (b) the distance the car travels while braking, assuming the acceleration is constant, and (c) the average velocity. ANSWERS (a) -4.38 m/s (b) 35.0 m (c) 8.75 m/s Example-2: GOAL Solve a problem involving two objects, one moving at con- stant acceleration and the other at constant velocity. a = -1.00 s ta = 0 PROBLEM A car traveling at a constant speed of 24.0 m/s passes a trooper hidden behind a billboard, as in next figure. One second after the speeding car passes the billboard, the trooper sets off in chase with a constant acceleration of 3.00 m/s. (a) How long does it take the trooper to overtake the speeding car? (b) How fast is the trooper going at that time? SOLUTION (a) How long does it take the trooper to overtake the car? Write the equation for the car's displacement: , Axar = Xar = tht + ař Take x, = 24.0 m, v, = 24.0 m/s, and acar 0. Solve + vt = 24.0 m + (24.0 m/s)t Xar= Nrite the equation for the trooper's position, taking - 0, v,= 0, and aer = 3.00 m/s: Kurooper = 4r0oper = }(3.00 m/s*) = (1.50 m/s³) Set oper=r and solve the quadratic equation. (The quadratic formula appears in Appendix A, Equation A.8.) Only the positive root is meaningful. 14 %3D (1.50 m/s)t 24.0 m + (24.0 m/s)t (1.50 m/s)12- (24.0 m/s)t- 24.0 m 0 1= 16.9 s (b) Find the trooper's speed at that time. Substitute the time into the trooper's velocity cquation: = v, + arooper = 50.7 m/s Vrooper =0 + (3.00 m/s®)(16.9 s) X voli REMARKS: equal ne and
Principles of Physics: A Calculus-Based Text
5th Edition
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Raymond A. Serway, John W. Jewett
Chapter2: Motion In One Dimension
Section: Chapter Questions
Problem 23P: The driver of a car slams on the brakes when he sees a tree blocking the road. The car slows...
Related questions
Question
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution!
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 2 images
Recommended textbooks for you
Principles of Physics: A Calculus-Based Text
Physics
ISBN:
9781133104261
Author:
Raymond A. Serway, John W. Jewett
Publisher:
Cengage Learning
University Physics Volume 1
Physics
ISBN:
9781938168277
Author:
William Moebs, Samuel J. Ling, Jeff Sanny
Publisher:
OpenStax - Rice University
Principles of Physics: A Calculus-Based Text
Physics
ISBN:
9781133104261
Author:
Raymond A. Serway, John W. Jewett
Publisher:
Cengage Learning
University Physics Volume 1
Physics
ISBN:
9781938168277
Author:
William Moebs, Samuel J. Ling, Jeff Sanny
Publisher:
OpenStax - Rice University