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Two simple problems

  • Thread starter Moneer81
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  • #1
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1. An astronaut on a strange planet finds that she can jump a maximum horizental distance of 30 m if her initial speed is 9m/s. What is the acceleration of gravity on the planet?

2. A projectile is fired in such a way that its horizental range is equal to three times its maximum height. What is the angle of projection?

thanks
 

Answers and Replies

  • #2
arildno
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3. What has Moneer81 done so far?
 
  • #3
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by the way this is not a HW I am not in school i am just practicing...

well for the first problem I am wondering if it could be done with the little information we have....

the second one is simpler if we substitute x = 3y into the equations of motion and try to get the x and y component of Vo (initial velocity) then the inverse tangent would give us the angle...

anyone has more detailed comments?
 
  • #4
arildno
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1. How is the maximal horizontal distance related to initial speed and acceleration due to gravity?
 
  • #5
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well acceleration due to gravity will have an effect on the vertical distance....not the horizental?
 
  • #6
arildno
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Moneer81 said:
well acceleration due to gravity will have an effect on the vertical distance....not the horizental?
But when&where the ball hits the ground again depends on the acceleration due to gravity, does it not?
 
  • #7
HallsofIvy
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Do you know the formulas for horizontal and vertical motion with a constant (vertical) acceleration?
 
  • #8
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yeah yeah you're right....got it :)
i think i was just thinking harder that I had to
 

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