There is a steel plate placed horizontally on the ground. There is a steel ball with mass m = 1kg at 3M above it. It moves vertically downward at the initial velocity V0 = 2m / s. assuming that the ball is subject to a constant air resistance f = 2n, there is no kinetic energy loss when the ball collides with the steel plate, and the ball finally stops moving (1) What's the speed of the first bounce? (2) The height of the first bounce? (3) What's the distance s it takes to stop?

There is a steel plate placed horizontally on the ground. There is a steel ball with mass m = 1kg at 3M above it. It moves vertically downward at the initial velocity V0 = 2m / s. assuming that the ball is subject to a constant air resistance f = 2n, there is no kinetic energy loss when the ball collides with the steel plate, and the ball finally stops moving (1) What's the speed of the first bounce? (2) The height of the first bounce? (3) What's the distance s it takes to stop?

(1) Just use the kinetic energy theorem, MGH FH = △ 0.5 * m * (the square of V) with a formula (H = 3)
(2) The second problem still uses the theorem of kinetic energy, but on the basis of the first sub problem (I record the answer of the above problem as V1), the countable formula (Mg + F) * H = 0.5 * m * (the square of V1) can be used to find H
(3) If we stop, the mechanical energy will be gone, because there is a non conservative internal force work determinant FS = 0.5 * m * (the square of V0) + MGH (H = 3)
The analysis process and algebraic formula of Sao Nian are all written on it. You can bring the number and the answer will come out. Young people, don't be so lazy