Question

Suppose a car waiting at red traffic light when the light turns to green the car accelerates uniformly at 2m/s within 6 sec then proceeds moving with a uniform speed at the movement the car starts at the green traffic light a truck passes by heading in the direction with a uniform speed of 10m/s. How long and how far from traffic light the car catches up with the truck?

Answer 1

$$x=0.5at^2+(at)(T-t), x=vT$$

$$0.5at^2+(at)(T-t)=vT$$

$$0.5(2)(6)^2+(2)(6)(T-6)=10T$$

The time will be

$$T=18\ s$$

The distance:

$$d=vT=(10)(18)=180\ m$$