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Jon Drake
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Are conservative forces always taken as internal forces?
Where? It might help if we could see the precise statement and its context.Jon Drake said:somewhere
Only conservative forces have a potential energy associated with them. The force acts so as to decrease the potential energy.Jon Drake said:Yes, and I still cannot understand the logic behind the statement.
That answer is plainly incorrect. If I lift a book from the floor and place it on a table, I have increased the potential energy of the book/earth system. But the force of my hand on the book is not conservative.Jon Drake said:''Where? It might help if we could see the precise statement and its context.''
It actually came as a question :-
Which of the following can increase the P.E. of a system?
a. Conservative Force
b. Nonconservative Force
c. Both
d. None
The answer was (a).
Set a puck at rest in the middle of an air hockey table. Attach a spring between the puck and a point on one end of the table. Attach a second spring between the puck and a point on the opposite end. Draw your system boundaries so that the first spring and the puck are part of the system but the second spring is not.Jon Drake said:Alright, my final question is, can conservative forces in any case increase the P.E. of a system?
Conservative forces are a type of force that depends only on the initial and final positions of an object, and not on the path taken between them. These forces are always internal to a system and do not cause any change in the total mechanical energy of the system.
A force is conservative if it meets two criteria: it is an internal force and its work is independent of the path taken. This means that if you move an object from one point to another, the work done by the force will be the same no matter which path is taken between the two points.
No, not all internal forces are conservative. Only forces that meet the criteria of being independent of the path taken and not causing a change in mechanical energy are considered conservative. For example, friction is an internal force that is not conservative as it dissipates energy in the form of heat.
Conservative forces do not affect the motion of an object in any way. This is because they do not cause any change in the total mechanical energy of the system. They only dictate the potential energy of an object at different positions.
No, conservative forces do not do any work on an object. This is because work is defined as a force acting on an object over a certain distance, and since conservative forces do not cause any change in the total mechanical energy, they do not do any work on the object.