$A$ hiker stands on the edge of a cliff $490 \ m$ above the ground and throws a stone horizontally with an initial speed of $15 \ m \ s^{-1}$. The speed with which it hits the ground is (in $m \ s^{-1}$)

$A$ particle is dropped from a height of $20\,m$ onto horizontal ground. There is wind blowing,due to which the horizontal acceleration of the particle becomes $6\,ms^{-2}$. Find the horizontal displacement of the particle until it reaches the ground (in $m$).

$A$ hiker stands on the edge of a cliff $490 \; m$ above the ground and throws a stone horizontally with an initial speed of $15 \; m/s$. Neglecting air resistance,find the time taken by the stone to reach the ground,and the speed with which it hits the ground. (Take $g = 9.8 \; m/s^2$).

$A$ missile is fired in the horizontal direction from a height of $20\,m$ at a speed of $1000\,m/s$. At what horizontal distance from the base will the missile land?

$A$ plane is flying horizontally at $98 \, m/s$ and releases an object which reaches the ground in $10 \, s$. The angle made by the object with the horizontal while hitting the ground is ......... $^o$.

$A$ ball is thrown upward from the top of a building at an angle of $30^{\circ}$ to the horizontal and with an initial speed of $20 \,m/s$. If the ball strikes the ground after $3 \,s$, then the height of the building is (acceleration due to gravity $g = 10 \,m/s^2$) (in $\,m$)