A man hits a golf ball (0.2 kg) which accelerates at a rate of 20 m/s2. What amount of force acted on the ball?

Newton taught us that Force = (mass) x (acceleration)

Force = (0.2) x (20) = 4 newtons.

Something to think а bout: The ball can only accelerate while the club-face

is in contact with it. Once the ball leaves the club, it can't accelerate any more,

because the force against it is gone.