Assess the validity (1 Viewer)

[o_0]

for the question asking to assess the validity of the experiment to measure the electrical resistance at -100 degrees celcius, how did you guys go about answering this?

 

[Implying]

for the question asking to assess the validity of the experiment to measure the electrical resistance at -100 degrees celcius, how did you guys go about answering this?

its not valid because the line of best fit is imprecise

 

[o_0]

its not valid because the line of best fit is imprecise

nice. by the way, is this question up for personal interpretation? or is there a definite answer?

 

[AAEldar]

It was given that the line was linear at room temperature, so it's unknown how it would be at the lower temperature. How I answered it anyway, plus the accuracy of the line of best fit.

 

[idunno1402]

by extrapolating the curve, ure assuming that the linear relationship holds true. that cant be valid, because for all we know, it could be a superconductor below -90 degrees

 

[Gangstar1]

what did you guys get for resistance?

 

[brent012]

It was given that the line was linear at room temperature, so it's unknown how it would be at the lower temperature. How I answered it anyway, plus the accuracy of the line of best fit.

+1. The range of the experimental data was too small to be able to presume its valid for -100 which is a massive jump, the formula thing they provided only held true for near room temperature (which the experimental data was) which tells us that the trend doesn't hold true for extreme temperatures like -100.

by extrapolating the curve, ure assuming that the linear relationship holds true. that cant be valid, because for all we know, it could be a superconductor below -90 degrees

Couldn't possibly be a super conductor, the type 2 super conductors with the highest critical temperature still have a critical temperature of around -140 celsius.

 

[telstrarobs]

Couldn't possibly be a super conductor, the type 2 super conductors with the highest critical temperature still have a critical temperature of around -140 celsius.

http://www.superconductors.org/254K.htm

-19 degrees Celsius superconductor.

 

[brent012]

http://www.superconductors.org/254K.htm

-19 degrees Celsius superconductor.

Haha wow +rep, that is awesome - pretty recent discovery though and I was just going off textbook examples. Besides that, i don't remember 100% but didn't the question specify the material was a metal alloy? All of these super conductors with relatively high critical temperatures are ceramics.

Edit: Oh wow on that site there is a super conductor with a critical temperature of 20 degrees celsius (positive!), that is incredible lol.

 

[telstrarobs]

Haha wow +rep, that is awesome - pretty recent discovery though and I was just going off textbook examples. Besides that, i don't remember 100% but didn't the question specify the material was a metal alloy? All of these super conductors with relatively high critical temperatures are ceramics.

Edit: Oh wow on that site there is a super conductor with a critical temperature of 20 degrees celsius (positive!), that is incredible lol.

Interesting. Now that I recall I do think it might have been a metal alloy.

 

[Fizzy_Cyst]

Question was

"The electrical resistance, R, of a piece of wire was measured at different temperatures, T. Near room temperature, the resistacne can be modelled by the equation R=mT+b

(b) Assess the validity of using the data from this experiment to estimate the electrical resistacne at -100 degC"

 

[brent012]

Question was

"The electrical resistance, R, of a piece of wire was measured at different temperatures, T. Near room temperature, the resistacne can be modelled by the equation R=mT+b

(b) Assess the validity of using the data from this experiment to estimate the electrical resistacne at -100 degC"

Lol sounds like some dodgy Benzoyl Peroxide face wash.

Anyway thanks, what do you think you would have had to say for full marks in this question?