Anita A. answered • 02/18/20

Instructor of Finite Mathematics at the Community College Level

Hello Emanuel,

y = 43t - 16t^{2} gives the height of the ball at the time, t, after the ball is released. This is a function about position - in this case, height.

The derivative of the position function yields the function for velocity of the object.

y' = 43 - 32t

The velocity at t = 2: 43 - 32(2) = -21 ft/ sec.

The velocity is negative because the object is slowing down from the original velocity due to the effect of gravity.

Regards,

Anita A.