A body falling for $2 \,seconds$ covers a distance $S$ equal to that covered in next second. Taking $g = 10\,m/{s^2},\,S =……….m$

When a ball is dropped into a lake from a height $4.9 \,m$ above the water level, it hits the water with a velocity $v$ and then sinks to the bottom with the constant velocity $v$. It reaches the bottom of the lake $4.0,s$ after it is dropped. The approximate depth of the lake is ………… $m$

Four marbles are dropped from the top of a tower one after the other with an interval of one second. The first one reaches the ground after $4$ seconds. When the first one reaches the ground the distances between the first and second, the second and third and the third and forth will be respectively

Two stones are thrown up simultaneously from the edge of a cliff $240\ m$ high with initial speed of $10\ m/s$ and $40\ m/s$ respectively. Which of the following graph best represents the time variation of relative position of the second stone with respect to the first ?

(Assume stones do not rebound after hitting the ground and neglect air resistance, take $g = 10\ m/ s^2$)
(The figures are schematic and not drawn to scale)

From a tower of height $H$, a particle is thrown vertically upwards with a speed $ u$. The time taken by the particle, to hit the ground, is $n$ times that taken by it to reach the highest point of its path. The relation between $H, u$ and $n$ is: