Question

100 POINTS

Answer 1

Answer:

3.8

Step-by-step explanation:

h(t) = -4.9 t² + v₀ t + h₀

Given that v₀ = 0 and h₀ = 70:

h(t) = -4.9 t² + 70

When the rock hits the ground, h(t) = 0.

0 = -4.9 t² + 70

4.9 t² = 70

t² = 14.3

t = 3.8

The rock hits the ground after 3.8 seconds.

Answer 2

Answer: t= 3.8secs

Step-by-step explanation:

h(t)=-4.9t^2+V0t+ h0

At initial velocity time is zero coz initial velocity is zero

H(t)= -4.9t^2+70

At final velocity h(t) is zero

70=4.9t^2

t^2=70/4.9

t^2=14.58

t=3.8secs