As shown in the figure, there is a flat car with length x = 1m and mass m = 10kg, which is still on a smooth horizontal plane. A small block with mass m = 4kg is placed at one end of the car. The dynamic friction coefficient between the block and the car is μ = 0.25. To make the block move to the other end of the car in 2S, what is the horizontal force F acting on the block? (g = 10m / S2)

As shown in the figure, there is a flat car with length x = 1m and mass m = 10kg, which is still on a smooth horizontal plane. A small block with mass m = 4kg is placed at one end of the car. The dynamic friction coefficient between the block and the car is μ = 0.25. To make the block move to the other end of the car in 2S, what is the horizontal force F acting on the block? (g = 10m / S2)

The motion of the car and the block is as shown in the figure. In the process of the block moving to the right end of the car, the displacement of the car is x1, the displacement of the block is X2, and the orientation to the right is positive. Taking the car as the research object, according to Newton's second law: μ mg = MA1 ① From the formula of uniform variable speed motion, we can get: X1 = 12a1t2 ② Based on Newton's second law, F - μ mg = ma 2 ③ From the formula of uniform variable velocity motion, we can get: x2 = 12a2t2 ④ From the meaning of the title: x2-x1 = x ⑤ From the data brought in by ①, ②, ④, ⑤, we can get: F = 16N A: the horizontal right tension applied on the small block should be 16N