Question

a ball is dropped form heigth of 80 feet and its elasticity of a ball is such that it rebounced 2/5 of the diatance.ti has fallen find tdistance at 5th bounche and total distance

Answer 1

The height on the nth bounce is

80 * (2/5)^n
These bounces form a geometric sequence, so
S5 = a(1-r^5)/(1-r)
where
a = 80
r = 2/5
since we are talking round trips for each bounce, double the sum, and subtract off the initial 80, since it was just a drop.
2*80(1 - (2/5)^5)/(1 - 2/5) - 80 = _____