Question

a body of mass 1.50 kg is dropped from a height of 12 m.Whatis the force acting on it during its fall?

Answer 1

Task. A body of mass 1.50 kg is dropped from a height of 12 m. What is the force acting on it during its fall?

Solution. If we ignore the air resistance, then a unique force acting on the body is the gravitation force. It is equal to

$F=mg,$

where $m=1.5$ kg the mass of the body and $g=9.81\,m/s^{2}$ is the acceleration due to gravity. In fact $g$ depends on the distance to the center of the Earth. But since the height is too small with respect to the radius of the Earth ($\approx 6400$ km), we can assume that $g$ is constant. Thus the force acting on the body is the same during its fall and is equal to

$F=1.5*9.81=14.715N.$