Question

If a ball is thrown with speed u meter per second square vertically upwards from a tower of height 80 meters if it reaches the ground in 3 seconds then what is the speed with which it is thrown vertically upwards? ( g=9.8 m/s)

Answer 1

Answer:

s=ut+

2

1

at

2

=19.6×5−

2

1

×9.8×5

2

=−24.5 m

Hence, height of tower =24.5m

v=u+at

=19.6−9.8×5=−29.4 m/s