A small object is projected horizontally from the top of a tower. If after 1 sec, The particle is at a height of 75 m from the ground, find its time of flight.

After 1 sec, vertical displacement of the particle =12gt2=12×10×(1)2m=5m∴ H=Height of tower =(5+75)m=80mIf T be the time of flight, then H=12gT2⇒T=2×8010 s=4sec⁡