Jump to content

Why do we base energy on work?


freefall

Recommended Posts

Instead of impulse, for example? They are both conserved.

 

When putting energy into an object, its \delta velocity is not directly proportional to the KE added (but is directly prop. to impulse). For this reason we say that a car needs more gas to accelerate by a constant amount the faster its moving (see other thread). But it doesn't take more impulse. If we based energy on impulse, we wouldn't say it takes more gas. Right?

 

Can someone explain?

thanks!

Link to comment
Share on other sites

I suspect you could develop an entire working system of physics based on impulse instead of work. You would have to redefine everything to work in the new system of definitions.

 

Nevertheless, the current definitions we have no seem to work pretty darn well at describing what is seen in nature.

 

And in that respect, even if you redefine the mathematics, nature will take no notice whatsoever. It will take a certain amount of gas to change the velocity a certain amount no matter if you call that quantity impulse, or work, or energy, or ether, or breakfast cereal, or sloths, or footballs. Nature takes no notice of what equations we use to describe nature. And the judgement we use on how good an equation is, is how well does that equation describe nature -- certainly not the other way around like you are trying to do.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.