A projectile is fired vertically upwards with an initial velocity $u$. After an interval of $T$ seconds a second projectile is fired vertically upwards, also with initial velocity $u$.

From the top of a tower, a ball is thrown vertically upward which reaches the ground in $6 \,s$. A second ball thrown vertically downward from the same position with the same speed reaches the ground in $1.5\, s$. A third ball released, from the rest from the same location, will reach the ground in…….. $s$.

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)

A stone is dropped from a certain height which can reach the ground in $5\, second$. If the stone is stopped after $3\, second$ of its fall and then allowed to fall again, then the time taken by the stone to reach the ground for the remaining distance is……..$sec$

A bead is free to slide down a smooth wire tightly stretched between points $A$ and $B$ on a vertical circle. If the bead starts from rest at $A$, the highest point on the circle