A professional race-car driver buys a car that can accelerate at +5.9m/s^2.The racer decides to race against another driver in a souped up stock-car.Both start from rest,but the stock-car driver leaves 1.0s before the driver of the race car.The stock

A professional race-car driver buys a car that can accelerate at +5.9m/s^2.The racer decides to race against another driver in a souped up stock-car.Both start from rest,but the stock-car driver leaves 1.0s before the driver of the race car.The stock
A professional race-car driver buys a car that can accelerate at +5.9m/s^2.The racer decides to race against another driver in a souped up stock-car.Both start from rest,but the stock-car driver leaves 1.0s before the driver of the race car.The stock car moves with a constant acceleration of +3.6m/s^2.
a.find the time it takes the race-car driver to overtake the stock-car driver.
b.Find the distance the two drivers travel before they are side by side.
c.find the velocities of both cars at the instant they are side by side.

A professional race-car driver buys a car that can accelerate at +5.9m/s^2.The racer decides to race against another driver in a souped up stock-car.Both start from rest,but the stock-car driver leaves 1.0s before the driver of the race car.The stock
一个专业的赛车手,买了车,可以在+5.9米/秒^2加速.赛车手决定和另一个司机经改装的一辆车进行比赛.都开始休息,然后改变车司机离开提前1.0秒的赛车司机.改装车的加速度+3.6米/秒^2.
A.找到赛车手超过改装车所花费的时间.B.找到两位车手并排在一起时,距离出行地的距离.C.找到两辆车在即时他们并排的速度.他们是并排的瞬间.
A.设超车所用时间为t,超车时刻二车到达同一位置.
赛车手：x1=a1t^2/2=5.9t^2/2
改装车：x2=a2(t+1)^2/2=3.6*(t+1)/2
到达同一位置：x1=x2
5.9t^2/2=3.6*(t+1)/2
t=3.5s
B.x1=5.9*3.5^2/2=36.1m
C.赛车手车速v1=a1t=5.9*3.5=20.65m/s
改装车车速v2=a2t=3.6*(3.5+1)=16.2m/s

一个赛车手买了一辆加速度达5.9m/s^2的新赛车，他决定去跟一个驾驶加大了马力的改装货车司机比赛。两辆车都从静止开始出发，货车司机早出发1.0秒，且货车以3.6m/s^2的加速度做匀加速运动，则求：
a。赛车司机追上货车司机所用的时间是多少？
b。赛车司机追上货车司机时，两车行驶的距离？
c。赛车司机追上货车司机时，两车的速度各为多少？

1、设赛车手追...

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一个赛车手买了一辆加速度达5.9m/s^2的新赛车，他决定去跟一个驾驶加大了马力的改装货车司机比赛。两辆车都从静止开始出发，货车司机早出发1.0秒，且货车以3.6m/s^2的加速度做匀加速运动，则求：
a。赛车司机追上货车司机所用的时间是多少？
b。赛车司机追上货车司机时，两车行驶的距离？
c。赛车司机追上货车司机时，两车的速度各为多少？

1、设赛车手追上货车司机的时间为：t，
则有：a1t^2/2=a2(t+1)^2/2，a1=5.9m/s^2，a2=3.6m/s^2
解得：t=3.5s
2、设：赛车手追上货车司机时，两车行驶的距离为：s
s=a1t^2/2=36.13m
3、设：赛车司机追上货车司机时，两车的速度各为：v1，v2
v1=a1t=5.9*3.5=20.65m/s
v2=a2*(t+1)=16.2m/s

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