As shown in the figure, the uniform ball with radius R and mass m is placed against the vertical wall, and there is a wood block with thickness h and mass m at the bottom left. If the friction is not considered, how much horizontal force F is used to push the wood block to make the ball leave the ground? What is the pressure on the ground?

As shown in the figure, the uniform ball with radius R and mass m is placed against the vertical wall, and there is a wood block with thickness h and mass m at the bottom left. If the friction is not considered, how much horizontal force F is used to push the wood block to make the ball leave the ground? What is the pressure on the ground?

When the ball just leaves the ground, the force on the ball and the block is shown in Fig. A and B. according to Fig. a, the equilibrium condition is: n1sin α - Mg = 0. ① and the geometric relationship is: sin α = R − hr. According to Fig. B, the equilibrium condition is: f-n2cos α = 0. ② f2-n2sin α - Mg = 0. ③ according to Newton's third law, N1 = N2 & nbs