$A$ body is thrown vertically upwards with a velocity of $35 \ m/s$ from the ground. The ratio of the speeds of the body at times $3 \ s$ and $4 \ s$ of its motion is (Acceleration due to gravity $= 10 \ m/s^2$)

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 rest from the same location will reach the ground in ........ $s$.

Two spherical balls having equal masses with a radius of $5 \, \text{cm}$ each are thrown upwards along the same vertical direction at an interval of $3 \, \text{s}$ with the same initial velocity of $35 \, \text{m/s}$. These balls collide at a height of $\ldots \ldots \ldots \, \text{m}$. (Take $g = 10 \, \text{m/s}^2$)

$A$ ball is thrown vertically upwards with an initial velocity $u$ and reaches its maximum height in $5 \,s$. The ratio of the distance travelled by the ball in the $2^{nd}$ and $7^{th}$ second is (assume $g=10 \,m/s^2$):

$A$ particle is thrown vertically upwards. It passes the same height at $t_1 = 2 \; s$ and $t_2 = 10 \; s$. The height is:

$A$ stone is dropped from a building of height $h$ and it reaches the ground after $t$ seconds. From the same building,if two stones are thrown (one upwards and one downwards) with the same velocity $u$ and they reach the earth's surface after $t_1$ and $t_2$ seconds respectively,then: