Free Fall Motion Under Gravity: Cases and Formulas
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Free fall motion is one of the most fundamental concepts in physics. When an object falls under the influence of gravity alone, without air resistance, it experiences a constant downward acceleration of 9.8 meters per second squared. Remarkably, all objects fall at the same rate regardless of their mass, as demonstrated by Galileo's famous experiment.
The motion of free falling objects can be described by three fundamental equations. The velocity increases linearly with time according to v equals g t. The distance fallen follows a quadratic relationship, h equals one half g t squared. And the relationship between velocity and height is given by v squared equals 2 g h. Let's visualize how height changes with time in a parabolic curve.
Free fall motion can be categorized into three main types based on initial conditions. First, objects dropped from rest with zero initial velocity. Second, objects thrown downward with positive initial velocity in the direction of gravity. Third, objects thrown upward with negative initial velocity, opposing gravity. In all cases, gravity acts downward with the same acceleration, but the initial velocity determines the specific motion pattern.
When an object is thrown upward, it follows a parabolic trajectory. The velocity decreases linearly due to gravity until it reaches zero at maximum height. The time to reach maximum height is v naught over g, and the maximum height is v naught squared over 2g. The total flight time is twice the time to maximum height. Let's observe how the ball moves up, stops momentarily, then falls back down.