A car moving along a straight highway with a speed of \(126\) km/h is brought to a stop within a distance of \(200\) m. How long does it take for the car to stop?

Two trains A and B of length \(400\) m each are moving on two parallel tracks with a uniform speed of \(72\) km/h in the same direction with A ahead of B. The driver of B decides to overtake A and accelerates by \(1\) m/s². If after \(50\) s, the guard of B just brushes past the driver of A, what was the original distance between them?
1. \(2000\) m
2. \(2250\) m
3. \(1200\) m
4. \(1250\) m

On a two-lane road, car \(A\) is travelling at a speed of \(36\) kmh^–1. Two cars \(B\) and \(C\) approach car \(A\) in opposite directions with a speed of \(54\) kmh^–1 each. At a certain instant, when the distance \(AB\) is equal to \(AC\), both being \(1\) km, \(B\) decides to overtake \(A\) before \(C\) does. What minimum acceleration of car \(B\) is required to avoid an accident?
1. \(1\) ms^–2
2. \(5\) ms^–2
3. \(2\) ms^–2
4. \(3\) ms^–2

A player throws a ball upwards with an initial speed of \(29.4 \text{ ms}^{- 1}\). What is the direction of acceleration during the upward motion of the ball?

A boy standing on a stationary lift (open from above) throws a ball upwards with the maximum initial speed he can, equal to \(49~\text{ms}^{-1}.\) How much time does the ball take to return to his hands? 
1. \(5\) s
2. \(10\) s
3. \(15\) s
4. \(7\) s