How Long Does a Pitch Take to Reach Home Plate?

[evelinm]

Homework Statement

If Mariano throws a 92mph cut-fastball to David Ortiz and strikes him out, how long does it take for the pitch to get to home plate? Compare this to a 81 mph changeup and a 67mph knuckle ball.

Homework Equations

d= v1*t+1/2(a)(t^2)

3. The Attempt at a Solution
d=0*t+1/2(92)(t^2)
d=0*t+46t^2
d=t^3+46
d/t^3=46

 

[RUber]

Mph indicates a speed (velocity) toward the plate. In you attempts, you have it in the acceleration place.
Assume no air resistance and acceleration should be 0.

 

[RUber]

Homework Statement

3. The Attempt at a Solution [/B]
d=0*t+1/2(92)(t^2)
d=0*t+46t^2
d=t^3+46
d/t^3=46

Those last two steps are not allowed. You can't randomly combine terms Review your algebra.