Question

Britney throws an object into the air with an initial vertical velocity of 27 feet per second, from a platform that is 10 feet above the ground.

How long will it take the object to hit the ground?
1 second
2 seconds
3 seconds
4 seconds

Answer 1

y = yo + Vot - (gt^2)/2

y = 10 + 27t - 16.087t^2 [I used g = 32.174 ft/s^2]

You can find y with the quadratic formula or probe with the different times given.

I tried with t = 2 s and found

y = 10 + 27(2) - 16.087 (4) = 10 + 54 - 64.348 = -0.348

Then that is the answer, t = 2s.