From a $200m$ high tower, one ball is thrown upwards with speed of $10m/s$ and another is thrown vertically downwards at the same speed simultaneously. The time difference of their reaching the ground will be nearest to

Q. A ball is thrown vertically upwards with a speed of $10m/s$ from the top of a tower $200m$ height and another is thrown vertically downwards with the same speed simultaneously. The time difference between them on reaching the ground is $(g=10m/s^2)$

Q. A ball is thrown vertically upwards with a speed of $10$ m/s from the top of the tower $400$ m high and another is thrown vertically down wards with the same speed simultaneously. The time difference between them in reaching the ground is ( $g=10m/s^2$ )

Q. A ball thrown vertically upwards with speed 'u' from the top of a tower reaches the ground in $9$ s. Another ball is thrown vertically downwards from the same position with speed 'u'. take $4$ s to reach the ground. Calculate the value of 'u'. $(Takeg=10{ms}^{-2})$

Q. A ball thrown vertically upwards at a certain speed from the top of a tower, reaches the ground after $9\text{seconds}$. Another ball thrown vertically downwards with same speed from the same tower reaches the ground in $4$ seconds. How much time will the ball take if it is just dropped from the tower?