# Kinetic Energy & Force

1. Feb 2, 2014

### pyreof88

Classical physics

2. Feb 2, 2014

### pyreof88

Im studying fumdamental concepts & looking at the relationship between kinetic energy & force. The ewuations seem similar, f=ma & k=mv²/2. Any input on the definiton of these to fundamental concepts & there relationship would be helpful.

3. Feb 2, 2014

### ZapperZ

Staff Emeritus
I don't think they look similar at all. They are certainly different dimensionally.

If you apply a force F on a mass m, over a distance x, then the amount of work done by that force will be equal to INCREASE in the kinetic energy of the mass. That is a simple illustration of the relationship between "force" and "kinetic energy".

Zz.

4. Feb 2, 2014

### pyreof88

Ok, so can i say it is required that a force be exerted on a body on order for it to gain or increase in its kinetic energy?

5. Feb 2, 2014

### pyreof88

Left you a line. New to this, so i will excise myself now.

6. Feb 2, 2014

### pyreof88

Also, if i may inquire for greater understanding, lets consider the physical phenomena of gases that have undergone combustion.
Is it accurate to say, regarding the kinetic energy of these combusted gases, that in the formula k=mv²/2, that the variable m represents the mass of the gas(es), v² equals the square of the velocity of the gas(es), and the variable k is the total kinetic energy of the combusted gas. k, according to the case presented would be of a spontaneous value right? Meaning a total value for a given point on time?

7. Feb 2, 2014

### ZapperZ

Staff Emeritus
I have no idea how this relates to your original question.

I think you should not use "gases" as your example, because a gas requires the understanding of the statistical nature of the system, something which I think you still do not grasp yet, i.e. have you learned statistical thermodynamics?. Try to use something simpler! What about the example I gave you? Did you understand that?

Zz.

8. Feb 2, 2014

### pyreof88

Yes, but you didnt look at my feedback which verified at least a vague understanding. Kinetic energy is that of a body in motion, this body, given proper circumstances, can exert a force on another body, thus transfering some or all of its kinetic energy.

9. Feb 2, 2014

### pyreof88

What about marbles on slides/rails? I could test acceleration, kinetic energy, gravitational potential energy & force.

10. Feb 2, 2014

### ZapperZ

Staff Emeritus
Only if you have learned about rotational energy.

Is there a reason for turning this into a circus?

Zz.

11. Feb 2, 2014

### pyreof88

Sorry Zapper, please bear with a student & not be insulting. It would be better if you could advise me of some productive activities that could aid me in the grasping of these concepts; being that you are so much more enlightened.

12. Feb 2, 2014

### sophiecentaur

I see where ZZ is coming from. If you want to advance in these things you need to get as simple as possible and not keep adding complication. To get a grasp, you should start with the very few basic formulae and then, if you want to verify them experimentally, it's essential to use the simplest possible models. If you don't do it that way you end up on a divergent path getting nowhere.

Google simple dynamics experiments or terms like that, if you want some ideas. You can then choose something to suit you.

13. Feb 2, 2014

### pyreof88

Thanks, its 'doin me' from here.

14. Feb 2, 2014

### sophiecentaur

Is that good?

15. Feb 2, 2014

### pyreof88

I found a decent textbook to give my studying some discipline. Thanks both of you for the feedback, its been disciplining.