一物体做匀加速直线运动，从某时刻开始计时，即此时t=0，已知在此之后1 s内的位移为1 m，由此可求出( )
A．这1 s内物体的平均速度
B．物体运动的加速度
C．这1 s内的末速度
D．物体在t="0.5" s时的瞬时速度
AD
题目分析：由v=s/t可知平均速度为1m/s，A对；由于不知道初速度的值，所以由运动学公式
不能确定加速度大小，同理也不能确定末速度大小，BC错；由中间时刻的瞬时速度等于平均速度可以确定物体在t="0.5" s时的瞬时速度，D对；
点评：要熟记匀变速直线运动公式，知道中间时刻的瞬时速度等于平均速度的结论，并能灵活应用
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