A stone is projected horizontally from the top of a vertical sea cliff 49m high, with a speed of 20ms^-1. Neglecting air resistance, calculate:
The time that it takes to reach the sea.
The Attempt at a Solution
I'm not sure whether i should be calculating v-final velocity via v² =u²+2as and using that to find t, ie. t=v-u/a
can anybody enlighten me please? thanks