Question

12. A 15,000 kg train car is rolling at a speed of 3.2 m/s. Compute the time required for a force

of 1200 N to stop the car.

Answer 1

40 s

Step-by-step explanation:

By Newton's 2nd law,

The rate of change of momentum is directly proportional to the unbalance force applied on the object,

By that you can get the equation,

F = ma ⇒ a = F/m

but a = (v-u)/t

So we get, t = (v-u)×m/F

where terms are in usual meaning

t =(3.2-0)×15000/1200 = 40 s