Question

A passenger in a train moving at an acceleration a', drops a stone from the window. A person, standing on the ground, by the sides of the rails, observes the ball following:

(a) Vertically with acceleration $\sqrt{g^2+a^2}$

(b) Horizontally with acceleration $\sqrt{g^2+a^2}$

(c) Along a parabola with acceleration $\sqrt{g^2+a^2}$

(d) Along a parabola with acceleration g

Answer 1

Whatever may be the acceleration of the train when the stone is throne from the train it will not acquire the horizontal acceleration of the train.

For horizontal

$x=vt$

For vertical

$y=\frac{1}{2}g{t}^2$

After combining

$y=\frac{1}{2}g\frac{x^2}{v^2}$

The above equation is the equation of the parabola.

Hence we can say that the stone will travel with a parabolic path with the acceleration g.