What is the free fall acceleration on the planet?

drummerdimitr
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Homework Statement



An astronaut on a strange planet finds that she can jump a maximum horizontal distance of 15 m if her initial speed is 3 m/s. What is the free fall acceleration on the planet?

Homework Equations



R=Vi^2sin2α/g

The Attempt at a Solution



15=9sin2α/g g=9sin2α/15
 
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Solution:
To have maximum range for a given initial velocity, her launch angle must be q0 = 45o. Her range then is R = (v02sin2q 0)/g' = v02sin90o/g' = v02/g'. We have g' = v02/R = 0.6m/s2.

Source: http://electron9.phys.utk.edu/phys135d/modules/m3/Projectile%20motion.htm

Scroll down to almost at the bottom of the page.
 
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Thanks for clarifying things up. I never knew that launching a projectile at 45 degrees would result in the greatest maximum range.
 
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