Question

Obtain the equation of motion for a body said to be under free fall

Answer 1

An object in free fall experiences an acceleration of -9.8 m/s/s. (The - sign indicates a downward acceleration.) Whether explicitly stated or not, the value of the acceleration in the kinematic equations is -9.8 m/s/s for any freely falling object.

Free Fall Motion. As learned in an earlier unit, free fall is a special type of motion in which the only force acting upon an object is gravity. Objects that are said to be undergoing free fall, are not encountering a significant force of air resistance; they are falling under the sole influence of gravity.

in free fall motion mass of the body goes approximately to zero but not exact zero

hence

f=ma

becomes

f=a