(adsbygoogle = window.adsbygoogle || []).push({}); William Tell must split the apple atop his son's head from a distance of 27.8 m. When he aims directly at the apple, the arrow is horizontal. At what angle must he aim it to hit the apple if the arrow travels at a speed of 34.6 m/s?

This sounds extremely simple, and I thought I got the answer at first. However, the homework engine at my college keeps saying I got the answer wrong.

Here's how I did it:

Vyot - 1/2gt^2 = 0

I solve for t, and get t=0 and t=2Vyo/g

I plug the second t in the x-cordinate for horizontal motion.

R = x = Vxot = Vxo(2Vyo/g) = (2VxoVyo)/g = (2V^2o sin(theta)o cos(theta)o)/g)

Eh, the work is messy but I'll skip down to my final deriviation and that is:

sin 2(theta) = Rg/(velocity initial squared)

(This is a common formula and the book uses this same formula to solve similar problems like this. And the funny thing is that I can follow their answers using that equation, but I apparently don't get a correct answer when I'm using it in this problem.)

I plugged in all the information I got and received 6.58 degrees and 84.3 degrees. There are two answers, and I typed both of them in the homework engine, and it said they were wrong. What am I doing wrong?

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# Homework Help: Projectile Motion Problem! This problem is completely evading me.

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