Kinematics Problem: How Far Will a Pitch Fall Vertically at 61.2 ft?

AI Thread Summary
The discussion revolves around a kinematics problem involving a baseball pitch thrown horizontally at 100.8 mi/hr and how far it falls vertically over a distance of 61.2 ft. The initial calculations converted the speed to 147.84 ft/s and determined the time to travel 61.2 ft as approximately 0.414 seconds. Using the kinematic equation, the calculated vertical drop was -0.8934 ft, which contradicts the expected range of 1.8 to 3.6 ft. The error was identified as using an incorrect value for gravity in ft/s², highlighting the importance of careful unit conversion in physics problems. This emphasizes the need for attention to detail in calculations.
Xaran
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Homework Statement


Directly from my homework.

One of the fastest recorded pitches in major-league baseball, thrown by Nolan Ryan in 1974, was clocked at 100.8 mi/hr. If a pitch were thrown horizontally with this velocity, how far would the ball fall vertically by the time it reached 61.2 ft away?

It wants the answer in ft.

Homework Equations


LaTeX Code: x = x_0 + v_0 t + (1/2) a t^2


The Attempt at a Solution



I started by converting mi/hr to ft/s and got 147.84 ft/s. So with this I figured that the ball would travel the 61.2 ft in 0.41396 seconds. From there I plugged it into the relevant equation to get y = 0 + (0)(0.41396) + (1/2) (-9.8) (0.41396)^2 to get an answer of -0.8934 ft.

The problem is that my question comes with an answer range that says my answer should fall somewhere between 1.8 and 3.6 ft. I've checked and double-checked the problem and I thought I've done it right, but I wanted to get a second opinion. Did I do the problem correctly and the answer range is just wrong, or am I missing something?
 
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Xaran said:

Homework Statement


Directly from my homework.

One of the fastest recorded pitches in major-league baseball, thrown by Nolan Ryan in 1974, was clocked at 100.8 mi/hr. If a pitch were thrown horizontally with this velocity, how far would the ball fall vertically by the time it reached 61.2 ft away?

It wants the answer in ft.

Homework Equations


LaTeX Code: x = x_0 + v_0 t + (1/2) a t^2

The Attempt at a Solution



I started by converting mi/hr to ft/s and got 147.84 ft/s. So with this I figured that the ball would travel the 61.2 ft in 0.41396 seconds. From there I plugged it into the relevant equation to get y = 0 + (0)(0.41396) + (1/2) (-9.8) (0.41396)^2 to get an answer of -0.8934 ft.

The problem is that my question comes with an answer range that says my answer should fall somewhere between 1.8 and 3.6 ft. I've checked and double-checked the problem and I thought I've done it right, but I wanted to get a second opinion. Did I do the problem correctly and the answer range is just wrong, or am I missing something?

Welcome to PF.

Shouldn't you be using a different value for gravity in ft/s2
 
And there's the small detail I overlooked. Its always something simple. Thanks! And thanks for the welcome. Just started my physics class this semester, so sometimes the little things like that escape me.
 
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