Calculating Distance Dropped of Horizontally Thrown Ball

[jessicax07]

Homework Statement

A pitcher throws horizontally a fast ball at 135 km/h toward home plate, which is 18.3 m away. Neglecting air resistance (not a good idea if you are the batter), find how far the ball drops because of gravity by the time it reaches home plate.

Homework Equations

v_ox = v_o
y = v_oy*t+1/2(-g)t²

The Attempt at a Solution

First I changed km/h to m/s and got 37.5. Then I found t and got 0.488s. Then I plugged it into the equation above and got 1.166. It was wrong though. Should it be negative or did I do it wrong?

 

[Mindscrape]

Hello. I'll preface my response here by saying that you'll probably get more replies to this type of problem if you post in the introductory physics forum. Advanced physics is usually, but not limited to, upper level undergraduate questions.

Yes, your answer should be negative based on the coordinate system you've made. Even the math says it will be negative.

 

[jessicax07]

thank you!