Finding g,time,&height with magnitude of velocity

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To determine the local gravitational acceleration (g) on an unknown planet, a crew member kicks a stone at 18.0 m/s, achieving a maximum range of 34.8 m at a 45° angle. The discussion revolves around using projectile motion equations to solve for g, time, and height. The key equation mentioned is g = Vo²sin(2θ)/R, which is derived from the principles of projectile motion. Participants emphasize the importance of calculating time for which the vertical displacement (y) is zero to find acceleration. The conversation highlights the need for clarity in applying physics equations to solve for unknowns in this scenario.
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Your spaceship lands on an unknown planet. To determine the local value of g , you ask a steel-toed crew member to kick a stone, and you find that if she kicks it at 18.0 m/s at various angles, the maximum range she can achieve is 34.8 m .
What is g (m/s)? time (s)? and height (m)?

I decided to use the knowledge of velocity given. Vox= Vocos\theta
I also knew that at 45° maximum distance may be achieved. However, I never did a problem with these unknowns in my physics class so I feel lost as to how to solve it. Any suggestions?
 
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I have worked through some problem solving methods that I think I need to go through to get to the next steps. I know that I need to solve for acceleration but I'm unsure as to how to do that with the equation y= yo+voyt+1/2at². Once I get the acceleration I believe I can just divide that figure by 9.8m/s² to get the value of g on the planet. Any suggestions are more than appreciated.

Thanks a ton!
 
Hi Kyle! :smile:
k2var2002 said:
I know that I need to solve for acceleration but I'm unsure as to how to do that with the equation y= yo+voyt+1/2at². Once I get the acceleration I believe I can just divide that figure by 9.8m/s² to get the value of g on the planet.

uhh? :confused:

the acceleration is the value of g on the planet. :wink:

Find it (using 45º) by finding t for which y = 0, then find the a for which x = 34.8 at that value of t. :smile:
 
g= Vo^2sin(2a)/R ? Does that make sense for an equation finding g?
 
k2var2002 said:
g= Vo^2sin(2a)/R ? Does that make sense for an equation finding g?

Do you mean g = v02sin2θ/R? How did you get that?

(btw, remember sin45º = 1/√2)
 
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