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5.2. An object, weighing 5kg falls freely from a 20m height (point A ) to the ground (point B), as shown in the diagram below. Initially the object has no velocity. It is assumed that no forces act on the object other than gravity. Determine the following (show ALL steps in calculations): 5.2.1. The potential energy at point A. 5.2.2. The potential energy at point B. 5.2.3. The kinetic energy at point A. 5.2.4. If the object falls at a velocity of 15m/s, determine the kinetic energy at point B