Need Help: Projectile Motion Problem

AI Thread Summary
The discussion revolves around solving a projectile motion problem involving a cannonball fired at a speed of 46.1 m/s at an angle of 44.1 degrees. The user initially used the equation Y=Yi+Viy(t)-1/2gt^2 to calculate the time of flight, arriving at an answer of 6.756 seconds. However, they received feedback from an online homework site indicating that this answer is incorrect, prompting a request for assistance. The user acknowledges a potential error in their calculations, specifically regarding the initial vertical velocity (Viy), which should be calculated using Viy = v * sin(θ). The discussion highlights the importance of correctly applying trigonometric functions in projectile motion problems.
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1. Assume you are a medieval knight attacking a castle with a cannon. The ball leaves the cannon with a speed of 46.1 m/s. The barrel's angle with respect to the ground is 44.1 degree, and you make a perfect hit on the tyrant's chamber which is at the same level as the cannon's muzzle. What is the time (in s) of flight of the cannon ball?

2. Y=Yi+Viy(t)-1/2gt^23.
Viy=46.1 m/2
Y & Yi=0
Theta Angle=44.1 degree
g=9.8m/s^2

I used this equation: Y=Yi+Viy(t)-1/2gt^2
0=0+46.1cos44.1(t)-1/2gt^2
4.9t^2/4.9t=33.106t/4.9t
t=6.756s

I drew the x/y coordinate system, right angle and sin/cos to help with solving the problem.
The online homework site says my answer is wrong. Please help. What am I doing wrong? Is it the equation or my algebra?
 
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viy is v*sinθ.
 
Thank you! I'll try that.
 

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