How Do I Calculate Uncertainty in Combined Measurements?

[scissors]

I'm doing a lab report right now, but am fuzzy on uncertainty in certain respects.

I have something like

d = 25 +/-2, d2 = 330 +/- 3, x = 55 +/- 6etc

how do I calculate the uncertainty, in another quantity, if it's like this

c = (d1 + d2)/x

Basically, how do I calculate the +/- part in c?

 

[stunner5000pt]

for both multiplication and division the uncertainties are added like this

$$\frac{\Delta c}{c} = \frac{\Delta d_{1}}{d_{1}} + \frac{\Delta d_{2}}{d_{2}} + \frac{\Delta x}{x}$$

 

[thepatientmental]

Hi there,

Uncertainty is an important concept in scientific measurements and it is essential to understand it for accurate reporting of results. In your case, the uncertainty in c can be calculated using the following formula:

Uncertainty in c = (Uncertainty in d1 + Uncertainty in d2 + Uncertainty in x)/x

In your given example, the uncertainties in d1, d2, and x are +/-2, +/-3, and +/-6 respectively. Therefore, the uncertainty in c would be:

Uncertainty in c = (2 + 3 + 6)/55 = 0.2

So, the final result for c would be:

c = (25 +/- 2 + 330 +/- 3)/55 +/- 0.2

I hope this helps clarify your doubts. If you have any further questions, please don't hesitate to ask. Good luck with your lab report!