two bodies of different mass when falls from same height, their initial velocities are same =0.
but acceleration will be same. =g
as we know g does not depend upon the mass of the object, g=GM/R2 where M= mass of earth, R= radius of earth, G= gravitational constant
so for all objects accl will be same . so velocity will also be same at any time.
but it does not happen because, of air friction of the atmosphere.
air friction will be different for diff body.
this friction will act in upward dir where as the weight will act in downward dir.
as a result the net force on the body will be different for different objects.so will be the acceleration.
net force=weight-friction due to air.
a<g and different for different objects.