题目.将质量为m的小球以水平速度v0抛出,小球在运动中受到的空气阻力与小球的速度成正比,f=-kv,k为比例常数.经过一段时间后,小球速度的偏向角为θ,求此时小球的速度v和运动的水平位移x.重力加速度为g.解法1:微元法将运动时间t等分成n段,则每一段的时间Δt=nt,令n→∞,则Δt→0 The problem is that mass m is thrown at a horizontal velocity v0 and the drag of the ball in motion is proportional to the velocity of the ball, f = -kv, where k is a constant of proportion.After a while, The deflection angle of the velocity is θ, then find the velocity of the ball v and the horizontal displacement of the movement x. The acceleration of gravity is g. Solution 1: The micro-element method divides the movement time t into n segments, then the time of each segment Δt = nt , Let n → ∞, then Δt → 0