在塔顶上将一物体竖直向上抛出,抛出点为A,物体上升的最大高度为20m
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发布时间:2023-08-27 11:54
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热心网友
时间:2024-08-13 12:19
x = at^2/2 = 20m = 10m/s^2*t^2 / 2
得t = 2(物体上升至最高点的时间)
则v0(起抛速度) = at = 10m/s^2*2s = 20m/s
10m = v0t - at^2/2 = 20t1 - 5t^2
解得t1 = 0.58s,t2 = 3.41s
x = v0t + at^2/2 = 10m = 20t + 5t^2
t1 = 4.45s,t2 = -0.45s,t2不符合实际舍去t2
所以时间为0.58s或3.41s或4.45s
热心网友
时间:2024-08-13 12:19
x = at^2/2 = 20m = 10m/s^2*t^2 / 2
得t = 2(物体上升至最高点的时间)
则v0(起抛速度) = at = 10m/s^2*2s = 20m/s
10m = v0t - at^2/2 = 20t1 - 5t^2
解得t1 = 0.58s,t2 = 3.41s
x = v0t + at^2/2 = 10m = 20t + 5t^2
t1 = 4.45s,t2 = -0.45s,t2不符合实际舍去t2
所以时间为0.58s或3.41s或4.45s
热心网友
时间:2024-08-13 12:19
x = at^2/2 = 20m = 10m/s^2*t^2 / 2
得t = 2(物体上升至最高点的时间)
则v0(起抛速度) = at = 10m/s^2*2s = 20m/s
10m = v0t - at^2/2 = 20t1 - 5t^2
解得t1 = 0.58s,t2 = 3.41s
x = v0t + at^2/2 = 10m = 20t + 5t^2
t1 = 4.45s,t2 = -0.45s,t2不符合实际舍去t2
所以时间为0.58s或3.41s或4.45s