Question

The projectile motion of an object can be modeled using s(t) = gt2 + v0t + s0, where g is the acceleration due to gravity, t is the time in seconds since launch, s(t) is the height after t seconds, v0 is the initial velocity, and s0 is the initial height. The acceleration due to gravity is –4.9 m/s2.

Answer 1

Answer: 0= -4.9t^2+19.6t+24.5

Step-by-step explanation:

Answer 2

S(t) =  -4.9t^2 + 19.6t + 24.5

when it reaches the ground s(t) = 0 


so we have -4.9t^2 + 19.6t + 24.5 = 0

solve this for t:-

-4.9(t^2 - 4t - 5) = 0

(t + 1)(t - 5) = 0

so required time t = 5 seconds  

answer 5 seconds