How tall must a building be for a dropped ball to hit the ground in 2 seconds?

(help! I'm in 8th grade and doing parabola and quadratic equations thank you)​

Respuesta :

Step-by-step Answer :

The height from which an object is dropped can be determined using the equation of motion under constant acceleration. In this case, the acceleration is due to gravity (approximately 9.8m/[tex]s^{2}[/tex])

The equation for the height (h) from which an object is dropped is given by:

h = [tex]\frac{1}{2}[/tex][tex]gt^{2}[/tex]

where:

  • - h is the height (in meters),
  • - g is the acceleration due to gravity (9.8m/[tex]s^{2}[/tex])
  • - t is the time the object is in free fall (in seconds).

You mentioned that the ball hits the ground in 2 seconds (t = 2).

h = [tex]\frac{1}{2}[/tex] · (9.8m/[tex]s^{2}[/tex]) · [tex](2s)^{2}[/tex]

h = [tex]\frac{1}{2}[/tex] · (9.8m/[tex]s^{2}[/tex]) · [tex]4s^{2}[/tex]

h = 19.6 m

So, the building must be at least 19.6 meters tall for a dropped ball to hit the ground in 2 seconds, neglecting air resistance.