# Homework Help: Is it significant

1. Mar 5, 2006

### sauri

If the values 1.59x10^-19 and 1.63x10^-19 came up for the same experiment can we say that these two values agree? and can we say the difference is significant?

The diff is only 4x10^-21..so what do you think? can we say the values agree?..and then what of the difference? is it significant?

2. Mar 5, 2006

### Hootenanny

Staff Emeritus
What experiment were you doing? Were you trying to find the charge on an electron?

3. Mar 5, 2006

### Hootenanny

Staff Emeritus
It also depends on the resolution of the equipment you are using...

4. Mar 5, 2006

### sauri

No this question is for any experiment. In the case where, if any general experiment were to produce such results can they be see as agreable?.

it can be for any experiment. And the experiment itself is not relavent. Only that the above values were obtained. So in the merit of the numbers itself can the be seen as agreeable? and what of the difference of the two figures?.

I do belive that that as the diiference is small (x10^-21) the values are in agreement and the difference is not significant. So am I correct?.

5. Mar 5, 2006

### Hootenanny

Staff Emeritus
The difference is in the order of $10^{-2}$, which I would say is fairly signifcant. However, If they are within the limits of the resolution of the equipment used, then you can say that they are in agreement.

6. Mar 5, 2006

### sauri

um..when i deduct (1.63x10^-19) - (1.59x10^-19), i get (4x10^-21). am i doing something wrong here?. Assuming that I am correct, and if these were two different meassurements of an experiment (charge of an electron for example) then I would be correct in assuming that the difference is not significant..right?

7. Mar 5, 2006

### Hootenanny

Staff Emeritus
yes you are correct, I'm not saying the you aren't correct, I was simpy stating the difference between the orders, i.e. -21 - - 19 = -2. Yes the difference could be considered not significant.

8. Mar 5, 2006

### sauri

oh thanks..also would it be more accurate to list the answers as (1.59+-0.01)x10^-19 and (1.63+-0.02)x10^-19?. As you can imagine the +and - in the equation should be one on top of each other, but I can't seem to type that in correcty. but apart from that, if the two values were to be written as above can we say that the two values are not in agreement?

9. Mar 5, 2006

### Hootenanny

Staff Emeritus
Why is the error different on the 1.63 one?

By the way, use \pm in latex to write $\pm$.