A jet airplane travelling at the speed of $500 km h^{-1}$ ejects its products of combustion at the speed of $1500 km h^{-1}$ relative to the jet plane. What is the speed of the latter with respect to an observer on the ground?

$1. 1000 km h^{-1}$
$2. 500 km h^{-1}$
$3. 1500 km h^{-1}$
$4. 2000 km h^{-1}$

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?
1. \(10.2\) s
2. \(9.6\) s
3. \(11.4\) s
4. \(6.7\) s

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 $29.4 m s^{-1}$. What is the direction of acceleration during the upward motion of the ball?

A particle in one-dimensional motion:

A man walks on a straight road from his home to a market \(2.5\) km away with a speed of \(5\) km/h. Finding the market closed, he instantly turns and walks back home with a speed of \(7.5\) km/h. What is the magnitude of the average velocity of the man over the interval of time \(0\) to \(30\) min?
1. \(6\) km/h
2. \(5\) km/h
3. \(5.6\) km/h
4. \(6.6\) km/h

The instantaneous speed is always:

A police van moving on a highway with a speed of $30 km h^{-1}$ fires a bullet at a thief’s car speeding away in the same direction with a speed of $192 km h^{-1}$. If the muzzle speed of the bullet is $150 m s^{-1},$ with what speed does the bullet hit the thief’s car? 

$\left(1\right) 103 m s^{-1}$
$\left(2\right) 105 m s^{-1}$
$\left(3\right) 101 m s^{-1}$
$\left(4\right) 102 m s^{-1}$

The figure gives the \((\mathrm{x-t})\) plot of a particle in a one-dimensional motion. Three different equal intervals of time are shown. The signs of average velocity for each of the intervals \(1,\) \(2\) & \(3,\) respectively are: