作业帮求高手解答这道选择题目~!~!
来源：学生作业帮 编辑：作业帮 分类：英语作业 时间：2024/07/04 19:27:03
求高手解答这道选择题目~!~!
a car is moving at a constant velocity when it is involved in a collision. The car comes to rest after 0.450s with an average acceleration of 65.0m/s^2 in the direction opposite that of the car's velocity. what was the speed, in km/h, of the car before the collision?
不是很明白题目的意思,求个高手来解答啊啊啊啊啊~~~
答案有5个其中一个~计算不到出来啊~有人会吗?
a)29.2km/s
b)44.8km/s
c)80.5km/s
d)105km/s
e)144km/s
a car is moving at a constant velocity when it is involved in a collision. The car comes to rest after 0.450s with an average acceleration of 65.0m/s^2 in the direction opposite that of the car's velocity. what was the speed, in km/h, of the car before the collision?
不是很明白题目的意思,求个高手来解答啊啊啊啊啊~~~
答案有5个其中一个~计算不到出来啊~有人会吗?
a)29.2km/s
b)44.8km/s
c)80.5km/s
d)105km/s
e)144km/s
意思是：汽车行动在恒定的速度时发生碰撞.汽车在0.450s停下来,做加速度与速度方向想反,为65.0m/s^2 的减速运动.问 汽车在碰撞之前速度多少km/h?
该题可以等效成为 速度为0的匀加速运动.
vt=v0+at=0+0.450*65.0=29.25m/s=105.3km/h
复制可耻
该题可以等效成为 速度为0的匀加速运动.
vt=v0+at=0+0.450*65.0=29.25m/s=105.3km/h
复制可耻