Conservation of Energy with an Ellipse

AI Thread Summary
Mechanical energy is conserved in an elliptical orbit due to gravity being a conservative force, which means that any change in kinetic energy (K.E.) is balanced by a change in gravitational potential energy (U_g). This conservation applies to the entire system of both bodies involved in the orbit. The discussion raises a question about whether the conservation principle remains valid when accounting for the motion of the larger planet, suggesting that the relationship may still hold despite added complexity. Ultimately, the conservation of mechanical energy in elliptical orbits is fundamentally linked to the nature of gravitational forces. Understanding these principles is crucial for analyzing orbital mechanics.
SprucerMoose
Messages
62
Reaction score
0
Gday,

This may be a trivial questiom, but I just cannot figure it out.

Why is mechanical energy conserved with an elliptical orbit? I understand that the mechanical energy of the system, i.e. both bodies, is conserved, but how is this isolated to the satellite's mechanical energy being conserved?
 
Physics news on Phys.org
Hang on, I think I figured it out.

Is it simply because gravity is a conservative force, thus any change in K.E. = change in Ug, therefore mech energy conserved?

Does this get more complicated if we consider the little motion of the larger planet, or does this simple relationship still hold?
 

Thread 'Average velocity as a weighted mean'

Hello everyone, Consider the problem in which a car is told to travel at 30 km/h for L kilometers and then at 60 km/h for another L kilometers. Next, you are asked to determine the average speed. My question is: although we know that the average speed in this case is the harmonic mean of the two speeds, is it also possible to state that the average speed over this 2L-kilometer stretch can be obtained as a weighted average of the two speeds? Best regards, DaTario
View full post »

Thread '1:1 versus 2:1 Mechanical Advantage debate'

The rope is tied into the person (the load of 200 pounds) and the rope goes up from the person to a fixed pulley and back down to his hands. He hauls the rope to suspend himself in the air. What is the mechanical advantage of the system? The person will indeed only have to lift half of his body weight (roughly 100 pounds) because he now lessened the load by that same amount. This APPEARS to be a 2:1 because he can hold himself with half the force, but my question is: is that mechanical...
View full post »

Thread 'Newton's first law?'

Some physics textbook writer told me that Newton's first law applies only on bodies that feel no interactions at all. He said that if a body is on rest or moves in constant velocity, there is no external force acting on it. But I have heard another form of the law that says the net force acting on a body must be zero. This means there is interactions involved after all. So which one is correct?
View full post »

Similar threads

Is Mechanical Energy Conservation Free of Ambiguity?
2
Replies
89
Views
10K
Conservative forces, Nonconservative forces and Potential Energy
Replies
9
Views
3K
Internal forces converting kinetic into potential energy (vice versa)
Replies
10
Views
2K
Law of Conservation of energy and Wnc
Replies
8
Views
2K
I Work-Energy Theorem for Moving Block and Spring System?
Replies
4
Views
2K
Is Mechanical Energy Conserved for Non-Conservative Forces?
Replies
14
Views
2K
I How do we analyze collisions involving accelerating objects?
Replies
4
Views
2K
B Conservation of momentum and conservation of energy details
Replies
30
Views
2K
B Conservation of momentum in a closed system
Replies
3
Views
2K
"External" potential energies strike back
Replies
6
Views
1K

Hot Threads

Recent Insights

Back
Top