Question

A truck traveling at a constant speed of 28 m/s passes a more slowly moving car. The instant the truck passes the car, the car begins to accelerate at a constant rate of 1.2 m/s^2 and passes the truck 545 m farther down the road. What was the speed of the car (in meters/second) when it was first passed by the truck?

Answer 1

Answer:

the velocity of car when it passes the truck is u = 16.33 m/s

Explanation:

given,

constant speed of truck  = 28 m/s

acceleration of car = 1.2 m/s²

passes the truck in 545 m

speed of the car when it just pass the truck = ?

time taken by the truck to travel 545 m

              time =$\dfrac{distance}{speed}$

              time =$\dfrac{545}{28}$

              time =19.46 s

velocity of the car when it crosses the truck

$S = ut + \dfrac{1}{2}at^2$

$545= u\times 19.46 + \dfrac{1}{2} \times 1.2 \times 19.46^2$

u = 16.33 m/s

the velocity of car when it passes the truck is u = 16.33 m/s