Jump to content

Relativity mix-up............


Harlequinne
 Share

Recommended Posts

1 joule is, among other things,

  • The work done on some object by a force of one newton as the object moves a distance of one meter, from [math]W=\oint \mathbf F \cdot d\mathbf l[/math]
  • The kinetic energy of a 2 kilogram mass moving at the non-relativistic velocity of 1 meter per second, from [math]KE=\frac 1 2 m v^2[/math]

 

These expressions have the same fundamental units and the same numerical value:

 

[math]1\,\text{joule} = 1\,\text{newton}\,*\,1\,\text{meter} = 1\,\text{kg}\,\text{meter}/\text{second}^2\,*\,1\,\text{meter} = \frac 1 2\,*\,2\,\text{kg}\,*\,(1\,\text{meter}/\text{second})^2[/math]

 

Energy has units of mass*velocity squared. The expression [math]mc^2[/math] has units mass*velocity squared -- energy.

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
 Share

×
×
  • 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.