Understanding Energy & Work: Seeking Help on Physics Theory

AI Thread Summary
Energy and work are fundamentally related, with the work-energy theorem stating that the work done on a particle equals its change in kinetic energy. For conservative forces, the work done is equal to the negative change in potential energy, indicating that the total mechanical energy (kinetic plus potential) remains constant. The discussion emphasizes the need for clear equations connecting kinetic and potential energy to work, particularly in the context of electric charges and gravitational forces. A basic understanding of these concepts is crucial for solving physics problems effectively. Additional resources and equations were suggested to aid in comprehension and application.
luis_alonzo
Messages
3
Reaction score
0
This is my first attempt seeking help on a forum so i hope its in the right place and i did look for similar questions but couldn't find any.

How does energy relate to work?
I have a couple of equations on my book but if you guys could like put here all the equations about energy and work. i know that probably includes a lot. I am studying electric charges, planets, and the more common stuff like falling objects and such.
what I am looking for is equations that relate kinetic and potencial enrgy to work and how does work relates to the net force of conservative and non conservative forces. i don't know a whole much of physics so if anyone could elaborate a litle on this i would appreciate greatly. i do have a basic understanding of math and calculus but i just don't get the theory involving this subject.
Thank you in advance.
 
Last edited:
Physics news on Phys.org
Hi Luis,

You can learn about energy by starting with the expression x=.5at^2
(The location of an object accelerating uniformly for a time t)

Next multiply both sides of the equation by a. This gives

ax=.5(at)(at) where you know that at=v because the acceleration is
constant.

So ax=.5v^2

Notice that time is not in this equation. That's important.
Also notice that the left side is called "work"
The right side is callled "kinetic energy"

If the acceleration is not constant then you replace ax with adx but
you've already learned the foundation.
 
thanks, still if anyone could give me a set of equations that i could use to solve execises. i don't mean to sound lazy because i have looked and its either very complicated to understand or not a big help.
thanks.
 
Exactly what do you find complicated?
 
luis_alonzo said:
How does energy relate to work?
\text{Energy} = \text{Work}

AM
 
its nothing specific, or rather its a lot of things, but they mostly relate to work. Maybe what I am asking for isn't simply stated but i guess i wanted a kind of an underlying theory.
 
And WHAT is the underlying "theory" in Newtonian physis?
What are the basic laws?
 
luis_alonzo said:
How does energy relate to work?
By the work energy theorem which states that the work done on a particle equals the change in kinetic energy of that particle. The work done on a particles which are acted upon for a conservative force equals the negative change of potential energy. The sum of the potential and kinetic energy for a conservative system is a constant of motion.
I have a couple of equations on my book but if you guys could like put here all the equations about energy and work. i know that probably includes a lot. I am studying electric charges, planets, and the more common stuff like falling objects and such.
See
http://www.geocities.com/physics_world/sr/work_energy.htm

Pete
 
Back
Top