PLEASE ANSWER!!! I WILL MARK YOU AS BRAINLIEST!!!! An object is launched straight up into the air with an initial velocity of 40 m/s, from a height 30 m above the ground. Assuming that gravity pulls it down, changing its position by about 4.9 m/s2, after how many seconds will the object hit the ground? Enter your answer as rounded to the nearest tenth, such as: 42.5

Respuesta :

Answer:

6.7 seconds

Step-by-step explanation:

Let's calculate the maximum height covered by the object

Max height= U²Sin²tita/2g

Where g is acceleration due to gravity

Max height= 40²(sin90)²/(2*9.81)

Max height= 1600/19.62

Max height=81.55 m

Total max height= 30+81.55

Total max height= 111.55 m

Time t it will take to travel from the max height at acceleration of 4.9 m/s²

S= ut + ½at²

u= 0 at Mac height

S= 111.5 m

111.5 = ½(4.9)t²

223/4.9= t²

45.5= t²

6.745 seconds= t

6.7 seconds= t