Question

Five race cars speed toward the finish line at the Jasper County Speedway. The table lists each car’s speed in meters/second. If each car has the same mass, which car will require the longest time to come to a full stop?
Car A Car B Car C Car D Car E
890 m/s 850 m/s 790 m/s 895 m/s 870 m/s

Answer 1

I think the answer would be Car C.

Answer 2

Answer:

CAR D

Explanation:

As we know that all cars have same mass so the deceleration of the car that will reduce its speed to rest is given as

$a = \frac{F}{m}$

so it will be same for all cars.

Now we know by kinematics as

$v_f - v_i = at$

so time taken by it to stop is given as

$t = \frac{v_f - v_i}{a}$

here since final speed of all cars is zero so we can say that more initial speed of car will take more time to stop the car.

So longest time will take by Car D