A ballon is ascending at the rate of `14 ms^-1` at a height of 98 m above ground when a packet is dropped from the balloon. After how much time and with what velocity does it reach the ground.

A 1.2 m tall girl spots a balloon moving with the wind in a horizontal line at a height of 88.2 m from the ground. The angle of elevation of the balloon from the eyes of the girl at any instant is 60^@ . After some time, the angle of elevation reduces to 30^@ (see fig.). Find the distance travelled by the balloon during the interval.

A ball is dropped a height h. The velocity of the ball when it reaches the ground is 10ms^-1 . Find h.

A man, 2 m tall, walks at the rate of 1 (2)/(3) m/sec towards a street light which is 5 (1)/(3) m above the ground. At what rate is the tip of his shadow moving? At what rate is the length of the shadow changing when he is 3 (1)/(3) m from the light.

A hundred metre sprinter increases her speed from rest unifromly at the rate of 1ms^-2 upto three-quarters of the total run and covers the last quarter with unifrom speed. How much time does she take to cover the first half, the second of the run?