Estimate the velocity achieved when you jump

AI Thread Summary
To estimate the velocity achieved when jumping straight up, one should use the height reached to calculate the change in potential energy and apply conservation of energy principles. The formula ymax=(v^2 sin^2 @)/2g is referenced, but the discussion emphasizes following the hint regarding energy conservation. The potential energy (Pe) and kinetic energy (Ke) at the jump's start and maximum height are crucial for the calculations. The user provided specific values, including a jump height of 50 cm and a mass of 61235 grams, leading to an estimated initial velocity of 1.72e6 cm/s. The discussion confirms the importance of using the correct formulas and energy principles to arrive at the solution.
leonne
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Homework Statement


estimate the velocity you achieve when you jump straight up hint use the height you reach jumping on Earth to estimate the change in potential energy and then use conservation of energy to estimate you initial kinetic energy

Homework Equations


ymax=(v^2 sin^2 @)/2g

The Attempt at a Solution



Can I just use that formula to solve for velocity or I have to use something else from what the hint is saying.
The main question is about, seeing if you can jump off an asteroid under your own power.
 
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leonne said:

Homework Statement


estimate the velocity you achieve when you jump straight up hint use the height you reach jumping on Earth to estimate the change in potential energy and then use conservation of energy to estimate you initial kinetic energy

Homework Equations


ymax=(v^2 sin^2 @)/2g

The Attempt at a Solution



Can I just use that formula to solve for velocity or I have to use something else from what the hint is saying.
You have the wrong formula. Follow the hint. What is the kinetic energy and potential energy immediately after jumping (h=0, v = vmax)? What is the kinetic energy and potential energy at maximum height? Write out the expression for total energy. Does it change?

AM
 
Hey thxs for the info so this is what i got
Pe= mgh Ke=1/2 Mv^2 height i got 50 cm mass 61235 grams and gravity is 98.1cm/s^2 (This is for astrophysics and some reason we can't use si units)

And using conservation of energy Pei+Kei= Pef +Kef

Pei would be 0 , we are trying to find kei Pef would be 3.00 e8 and Kef would be the same as Pef Then just solve for Kei =9e16 then plug that in the formula to find the initial velocity =1.72e6

Did i do this right?
 
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