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Average Speed in Projectile Motion and in General Motion of a Particle

DOI: 10.4236/jamp.2018.67130, PP. 1540-1548

Keywords: Average Speed, Time-Average, Space-Average, Instantaneous Speed, Projectile Motion, General Motion

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We calculate the average speed of a projectile in the absence of air resistance, a quantity that is missing from the treatment of the problem in the literature. We then show that this quantity is equal to the time-average instantaneous speed of the projectile, but different from its space-average instantaneous speed. It is then shown that this behavior is shared by general motion of all particles regardless of the dimensionality of motion and the nature of the forces involved. The equality of average speed and time-average instantaneous speed can be useful in situations where the calculation of one is more difficult than the other. Thus, making it more efficient to calculate one by calculating the other.


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