What is the percentage uncertainty in V when L1-L2 is 30?

[Rohan1997]

Homework Statement

My homework question says: the uncertainty in length 1 is +/- 0.1 and in length 2 is +/- 0.1 : calculate the percentage uncertainty in V where V

L1-L2 is 30

Homework Equations

V= (1/(L1-L2))^0.5 where L is the length[/B]

The Attempt at a Solution

So what I did was add the two uncertainties to get +/- 0.2
I then worked out percentage uncertainty by doing 0.2/30 *100%

and then I multiplied my answer by 0.5 since it is being square rooted.

Is this correct or have I made a mistake somewhere in my method?

 

[BvU]

If you have learned to add uncertainties linearly, then: yes (correct) and no (no mistake)

 

[Rohan1997]

If you have learned to add uncertainties linearly, then: yes (correct) and no (no mistake)

thanks :)

 

[BvU]

Your welcome, but mind you: it's an opinion: there's no guarantee

And: If the uncertainty in L₁ - L₂ is 0.2, why isn't this difference written as 30.0 ?

 

[Rohan1997]

Your welcome, but mind you: it's an opinion: there's no guarantee

And: If the uncertainty in L₁ - L₂ is 0.2, why isn't this difference written as 30.0 ?

don't know what your talking about sorry