Ive got a gravitational Potential Energy Question

AI Thread Summary
The discussion centers on understanding gravitational potential energy and interpreting a related graph. A user seeks clarification on the graph's representation of potential energy versus distance and questions the labeling of energy points E1 and E2. They mention the formula for gravitational potential energy, U = -GMm/r, and express confusion over a friend's solution to a problem involving a 25 kg mass in orbit 520 km above Earth. The user emphasizes the need for a clearer explanation of the graph and the calculations involved. Overall, the thread highlights the complexities of gravitational potential energy and the importance of accurate graph interpretation.
clearlyjunk
Messages
3
Reaction score
0
HEre is the page! http://img190.imageshack.us/i/backofgravitationalpote.jpg/

Homework Statement


http://img190.imageshack.us/i/backofgravitationalpote.jpg/
Qeustions at that pg


1.Examine teh graph

2.Calculate the change in potential of a 25 kg mass which is placed into orbit 520 km above the surface of teh earth.


Homework Equations



1.Please explain teh graph!
2.What the fudge is going on with the eg1 and eg2

The Attempt at a Solution



My friend did the solution and passed a copy of his sheet to me. I don't understand why stuff is happening.
 
Physics news on Phys.org
The formula for gravitational potential energy is U = \frac{-GMm}{r}. The graph is just U vs. r so U = \frac{-A}{r} where A = GMm and r goes from 0 to infinity (the smallest physical value of r is 0). Also, in the graph r1 should correspond to E1 and r2 should correspond to E2 so the graph is labeled wrong.
 
Last edited:

Thread 'Errors and significant figures'

I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
View full post »
Thread 'A cylinder connected to a hanging mass'

Thread 'A cylinder connected to a hanging mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
View full post »

Similar threads

Gravitational Potential Energy questions near the surface of a planet
Replies
8
Views
2K
Deriving gravitational potential energy -- mistake
Replies
9
Views
2K
Gravitational potential energy of a coupled pendulum
Replies
6
Views
2K
Potential energy of ball thrown upwards
Replies
5
Views
14K
Calculating Gravitational Potential
Replies
3
Views
1K
Change in gravitation potential energy in space
Replies
5
Views
2K
Distance in Electric versus Gravitational potential energy
Replies
8
Views
2K
Gravitational potential energy
Replies
8
Views
2K
GCSE Physics : Temperature & Gravitational potential energy
Replies
2
Views
2K
Potential gravitational energy coordinate axis
Replies
6
Views
1K

Hot Threads

Recent Insights

Back
Top