AP物理题 有关自由落体，在线等~A stone is thrown straight up from the top of a building with initial velocity 40ft/sec and hits the ground 4 sec later. The height of the building, in feet, isA 88 B 96 C 112 D 128 E 144中文翻译：一块石头从楼顶竖直向上扔去，初速度为40尺/秒，石头在4秒后落到地面。求问楼的高度。
2019-06-19
AP物理题 有关自由落体，在线等~
A stone is thrown straight up from the top of a building with initial velocity 40ft/sec and hits the ground 4 sec later. The height of the building, in feet, is
A 88 B 96 C 112 D 128 E 144
中文翻译：
一块石头从楼顶竖直向上扔去，初速度为40尺/秒，石头在4秒后落到地面。求问楼的高度。
优质解答
以地面为原点.
x=-1/2 gt^2+v0t+h
带入x=0,g=32ft/s^2 ,t=4s,v0=40ft/s
解得h=96ft
以地面为原点.
x=-1/2 gt^2+v0t+h
带入x=0,g=32ft/s^2 ,t=4s,v0=40ft/s
解得h=96ft