Energy needed for pluto to escape earth surface

Click For Summary

Homework Help Overview

The discussion revolves around calculating the energy required for an object to escape from the surface of Pluto, relative to the energy needed to escape from Earth. Participants are examining the appropriate formulas and concepts related to gravitational potential energy and escape velocity.

Discussion Character

  • Conceptual clarification, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants are discussing the formula (Mp*Re)/(Me*Rp) and questioning its correctness in the context of energy calculations versus velocity ratios. There are attempts to clarify the relationship between kinetic energy, potential energy, and escape energy.

Discussion Status

Some participants have provided guidance on the formula's correctness, while others are exploring the derivation of the expression and its application to the problem. There is an ongoing examination of the distinction between energy and velocity in the context of the original question.

Contextual Notes

Participants have noted a misunderstanding regarding the focus on energy rather than velocity, which has led to some confusion in the discussion. The original poster has a grace period for answers within 5% of the correct value.

jperk980
Messages
47
Reaction score
0
Calculate the amount of energy required to escape from the surface of the following bodies, relative to that required to escape from the surface of Earth.(a) Pluto

I keep on getting the same answer to be .011092137 but according to the website i am working on that is not correct. I used the mass of Earth to be 5.98e24, mass of Pluto is .002*5.98e24 and the radius's of Earth is 6.378e6 and Pluto is 1.15e6. I understand that (Mp*Re)/(Me*Rp) should be the correct formula.

If you get a different answer please help me achieve the answer you got because i have been trying many different solutions and still have not been able to figure out the question. I have a 5% grace period which all answers within 5% are correct.
Thank you
 
Physics news on Phys.org
Your formula looks correct.
 
jperk980 said:
I understand that (Mp*Re)/(Me*Rp) should be the correct formula.
This is the correct formula for what? Ratio of velocities? I don't think so.

Where did you get this expression, and can you derive it? You should be able to, if you want to understand the problem completely. Try doing that, and I think you'll see what you need to do to correct the expression that you gave above. If you're not sure how to do that, just ask.
 
Doc Al said:
Your formula looks correct.
oops. We crossed responses.

Are you sure he's correct? For ratio of escape velocities? KE is proportional to v^2 and PE is proportional to M/R, right? Unless I missed a radical sign somewhere, that's not what I get ... :confused:
 
The question asked for energy, not velocity:
jperk980 said:
Calculate the amount of energy required...
 
In original post the question is about energy, not velocity
jperk980 said:
Calculate the amount of energy required to escape from the surface of the following bodies, relative to that required to escape from the surface of Earth.(a) Pluto
 
aughh! SORRY! I mis-read it, as you've noticed ... and I keep crossing messages.

Never mind me!

(except that I now agree with jperk's original answer)
 

Similar threads

Variation of escape velocity with equal surface gravity
  • · Replies 7 ·
Replies
7
Views
1K
Calculating Escape Velocity for Earth: Where Am I Going Wrong?
  • · Replies 2 ·
Replies
2
Views
2K
High School Is the barycentre of the Pluto - Charon system also the L1 point?
  • · Replies 3 ·
Replies
3
Views
2K
Confusion regarding surface tension direction and force balance
  • · Replies 39 ·
2
Replies
39
Views
3K
Intuition for why escape velocity doesn't depend on angle
  • · Replies 9 ·
Replies
9
Views
2K
Need help finding energy for escape velocity
  • · Replies 5 ·
Replies
5
Views
3K
Undergrad Atmospheric escape parametre statistics
  • · Replies 1 ·
Replies
1
Views
2K
What will be the energy required to make 1 electron escape?
  • · Replies 5 ·
Replies
5
Views
2K
Calculating Energy Ratios: Moving Mass to and from Earth's Core
  • · Replies 2 ·
Replies
2
Views
1K
Escape velocity of an Earth-Moon system
  • · Replies 3 ·
Replies
3
Views
2K