Max Range Lab: Solving the Units Problem

AI Thread Summary
The discussion focuses on resolving a unit mismatch in a lab report analyzing maximum projectile range. The user is using a range equation that includes initial velocity, angle, gravitational acceleration, and height, but encounters unit inconsistencies. Eliminating height from the equation improves unit conformity but still results in a 20% discrepancy from expected data. A suggested solution involves adjusting the equation to incorporate V0 cosθ within the radical, leading to a more accurate calculation of range. This adjustment is expected to yield a larger calculated range that aligns better with experimental results.
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Homework Statement



I am doing a lab report where I have to find a maximum range and at what angle it occurs. For the range equation I am using a range equation with the initial velocity, theta, g and h as variables. There clearly is a problem since my units do not match up, and I can't find what it is. h has to be zero since the projectile was shot at h=0. Eliminating h still doesn't solve the units problem, but the answer does conform more with my data, but still is 20% off.

Homework Equations



V0=4 m/s
theta=45 deg.

The Attempt at a Solution


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When you bring the term V0 cosθ inside the radical, and it becomes V02 cos2θ, the first term in the radical should be
V02 cos2θ * V02 sin2θ
= V04 sin2θ cos2θ​
and then the units agree. (And transform to sin22θ as appropriate, of course.)

This will make your calculated R larger.
 

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