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An athlete runs three-fourths of the way around a circular track. Which of the following statements is true?

a. His average speed is greater than the magnitude of his average velocity.
b. The magnitude of his average velocity is greater than his average speed.
c. His average speed is equal to the magnitude of his average velocity.
d. His average speed is the same as the magnitude of his average velocity if his instantaneous speed is constant.
e. None of the above statements are true.

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Rodolfo
RodolfoLv5
10 Mar 2019
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Related textbook solutions

Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

Related questions

  1. An object moves clockwise with decreasing speed around an oval track. The velocity vectors at points G and H arc shown.

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c. Describe how you would determine the acceleration (direction and magnitude) at point

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d. Copy  and  (placed "tail-to-tail") in the space at right. How does the angle between the acceleration and velocity vectors compare to 900? (i.e., Is the angle greater than, less than, or equal to 90°?)

e.

Generalize your results above and from tutorial to answer the following question:

For an object moving along a curved trajectory, how does the angle between the acceleration and velocity vectors compare to 90° if the object moves with (i) constant speed, (ii) increasing speed, and (iii) decreasing speed?

 


Object A collides on a horizontal frictionless surface with an initially stationary target, object X. The initial and final velocities of object A are shown. The final velocity of object X is not given.

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