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# Random Uncertainty watch

1. In my experiment I am finding the values of resistance at certain temperatures with a thermistor. My question is would there be a random uncertainty? I have 11 readings, value of resistance at 0 degrees is 300 kΩ and the value at 90 degrees is 4.5 kΩ.

I know there is a random uncertainty when you take readings of the same thing (I.e. measuring the time taken for a ball to drop from a certain height) but will there be a random uncertainty as I'm not measuring the same value each time?

Sorry if I haven't explained it that well.
2. (Original post by munchen102)
In my experiment I am finding the values of resistance at certain temperatures with a thermistor. My question is would there be a random uncertainty? I have 11 readings, value of resistance at 0 degrees is 300 kΩ and the value at 90 degrees is 4.5 kΩ.

I know there is a random uncertainty when you take readings of the same thing (I.e. measuring the time taken for a ball to drop from a certain height) but will there be a random uncertainty as I'm not measuring the same value each time?

Sorry if I haven't explained it that well.
Did you have an electronic reader for the resistance?
3. (Original post by joostan)
Did you have an electronic reader for the resistance?
Yes.
4. (Original post by munchen102)
Yes.
Then probably not.
5. (Original post by munchen102)
In my experiment I am finding the values of resistance at certain temperatures with a thermistor. My question is would there be a random uncertainty? I have 11 readings, value of resistance at 0 degrees is 300 kΩ and the value at 90 degrees is 4.5 kΩ.

I know there is a random uncertainty when you take readings of the same thing (I.e. measuring the time taken for a ball to drop from a certain height) but will there be a random uncertainty as I'm not measuring the same value each time?

Sorry if I haven't explained it that well.
There will be uncertainty in any measurement.
How can you be certain of the temperature of the thermistor?
How did you measure temperature?
6. (Original post by Stonebridge)
There will be uncertainty in any measurement.
How can you be certain of the temperature of the thermistor?
How did you measure temperature?
Yes I'm using the scalar, calibration etc, just wondered whether I would include the random.
7. I have another question. I've plotted a graph of resistance vs temperature and this is it:

I have then enlarged a portion of the graph to find a certain temperature change at a two specific resistances:

The faded vertical lines indicate the change in temperature.

My question is, I've used a thermometer (+/- 1 degree uncertainty) but the temperature change is 0.32*C so how would I find the uncertainty in that? (My scalar uncertainty is greater than the value itself)
8. Anyone? My write up deadline is Monday

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