Ladies and gentlemen, we have a winner! To mix things up a bit, I decided to simulate this one.

^{1 }I used*Mathematica*for the simulation. There is a gravitational force*F*=

*m g*

on the tennis ball. Here,

*m*= 57 g is the mass of the ball and

*g*= 9.8 m/s

^{2 }is the acceleration due to gravity. The wind can be represented by a drag force

*F*=

*C A ρ v*

^{2}/ 2,

where

*C*= 0.3 is the drag coefficient,

*A*= 0.0036 m

^{2}is the cross-sectional area of the ball,

*ρ*= 1.2 kg/m

^{3}is the density of air, and

*v*is the velocity of the ball relative to the air. I made an animation of the simulation below.

It turns out you need a wind of about 45 mph. Congratulations to our winner!

[1] I know, I know...it's

*supposed*to be an estimation. You know that scene in

*Raiders of the Lost Ark*when Indiana Jones shoots the sword-wielding guy? Well, it turns out that was

*supposed*to be an elaborately choreographed fight scene, but Harrison Ford had severe diarrhea that day so he called an audible. Spielberg loved it, so it stayed in the movie. Why do I bring this up? Do I have severe diarrhea? No, but I was tired, lazy, and in the mood to simulate/animate something. Plus, we had a lot of good estimates and I wanted to make sure my number was halfway decent. Besides, I thought this one deserved a stick-figure animation. Long story short, this was my "shooting the swordsman" moment.

*Aaron Santos is a physicist and author of the books*

**How Many Licks? Or How to Estimate Damn Near Anything**and**Ballparking: Practical Math for Impractical Sports Questions**. Follow him on Twitter at @aarontsantos.

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