Answer-
According to the given question-
- We
know that the spinning balls also generates lift force and this is
called Magnus effect and the force due to spin is called Magnus
force.
-
when a ball with top spin, then there is forward velocity in their
upper surface compared to center of ball while there is backward
velocity on lower surface compared to center of ball.
-
But all molecules of air have backward velocity compared to the
center of ball. When air molecules strike the lower surface of the
ball then this cause slow down of the ball because both air and the
lower surface are in same direction compared to the center of
ball.
-
When air molecule strike with top surface then it causes slow down
of ball because top surface is moving opposite direction of air
compared to the center of ball.
- So
the velocity of air on top surface is less than bottom surface and
due to which there will be less pressure on lower surface because
there is fast moving air molecule and this causes a lift force in
downward direction on the ball.
So
the statement
A topspin will result in less pressure on the bottom of the
ball is true