竖直上抛一物体,初速度为30m/s,求:物体在2s末,4s末,6s末的高度及速度
高度:
X1=Vo*t1+½at1²
=Vo*t1-½gt1²
=30×2-0.5×10×4
=40m
X2=Vo*t+½at²
=Vo*t2-½gt2²
=30×4-0.5×10×16
=40m
X3=Vo*t3+½at3²
=Vo*t3-½gt3²
=30×6-0.5×10×36
=0
速度:
V1=Vo+at1
=Vo-g*t1
=30-10×2
=10m/s
V2=Vo+at2
=Vo-g*t2
=30-10×4
=-10m/s
V3=Vo+at3
=Vo-g*t3
=30-10×6
=-30m/s