Throw stones and paper balls with the same force.

The landlord must find out! There is a difference between throwing with the same strength and throwing with your arms!

First of all, the same force still acts on the stone and paper ball at the same distance, and the work is the same, that is, the kinetic energy obtained by the stone and paper ball! Because the mass of stone is greater than that of paper, the speed x of stone is smaller, and the two fall at the same height, and the stone flies closer!

Explain again: the mass of the arm is much greater than that of the stone and paper, so the mass of the stone and paper is not considered. When they finally leave their arms, they get the same speed, but the mass of stone is greater than that of paper, so the kinetic energy of stone is greater and it can fly farther under the same air resistance!