How Do You Calculate the Initial Velocity of a Projectile?

AI Thread Summary
The discussion revolves around calculating the initial velocity (Vo) of a projectile launched at an angle of 28.0 degrees from a height of 46.0 meters. The projectile impacts the ground with a speed of 1.95 times the initial velocity. The user initially applies the kinematic equation for vertical motion but arrives at an incorrect answer of 37.9 m/s. They express frustration over the mistake and seek alternative methods or insights to solve the problem correctly. The conversation emphasizes the importance of accurately applying physics equations and understanding projectile motion dynamics.
jennypear
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projectile is fired w/an angle of 28.0degrees above the horizontal and from height 46.0m agove the ground. the projectile strikes ground w/a speed of 1.95xVo. Find Vo

I started using the eqution
(Vfy)^2=(Voy)^2+2*Ay*(delta Y)

Voy=Vosin(theta)=.47Vo
Vfy=1.954*Vosin(theta)=.92Vo

(.92Vo)^2=(.47Vo)^2+(2*-9.8*-46)
Vo=37.9

but my answer is wrong and I can't think of another way to answer the problem...Any ideas?

Thanks for your time!
 
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