What Went Wrong? Calculating the Max Height of a Projectile at a 30 Degree Angle

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SUMMARY

The discussion focuses on calculating the maximum height of a projectile launched at a 30-degree angle with an initial speed of 0.714 m/s. The participant utilized the kinematic equation V² = V₀² + 2ad to derive a height of 19.49 meters, which was deemed impractical. The error was identified in the application of the equation, specifically in the calculation of the vertical component of the initial velocity and the interpretation of the results. Correctly, the maximum height should be calculated using d = V₀² / (2g), leading to a more realistic value.

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Bobbert
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Homework Statement


Find the max height of a projectile fired at an angle of 30 degrees if it's inital speed is 0.714m/s.
(this is a lab so I have other data that might be needed)

Homework Equations


V22=V12+2ad

The Attempt at a Solution


V22=V12+2ad
0=(0.714sin30o)2+2(-9.81)(d)
d=19.62-0.127449
d=19.49m

Now this answer is not practical at all. There is no way my projectile went that high. Maybe a couple meters, but not 19.5m. Where did I go wrong?
 
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Bobbert said:
3. The Attempt at a Solution
V22=V12+2ad
0=(0.714sin30o)2+2(-9.81)(d)
d=19.62-0.127449

d=19.49m

Now this answer is not practical at all...

Maybe it's your math that isn't practical?

Shouldn't you get a result that is a small number divided by a big number?
 
If v2=0

then 0=V12-2(9.81)d

d=\frac{V_1^2}{2(9.81)}
 
wow, it is way to late. How did I mess that up.
 

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