How to Find Speed From Distance & Mass

    Determine the time, or initial velocity. If that is not available, then the calculation can only be made assuming that it started from rest.

    Use the equation, vf^2 -- vi^2 = 2ad, where "vf" represents the final velocity, "vi" is the initial velocity, "a" is acceleration and "d" equals the displacement.

    Note that acceleration equals -9.8 meters per second since it is a free fall. The mass amount does not change the formula because all objects accelerate at the same rate when falling downward.

    Use the formula, velocity = mass x acceleration, and calculate the final velocity by following these steps:

    vf^2 - 0 = 2(-9.8)(-0.05)

    vf = root(0.98)

    vf = 0.99 m/s

    Take the final velocity/speed amount, or 0.99 meters per second, and plug it into the basic formula for speed:

    speed = distance/time.

About the Author

Kimberly Dyke is a Spanish interpreter with a B.A. in language and international trade from Clemson University. She began writing professionally in 2010, specializing in education, parenting and culture. Currently residing in South Carolina, Dyke has received certificates in photography and medical interpretation.