please help me with this: The resistivity of a copper rod 50ft long and 0.25 in. in diameter is 1.76 x 10 ^-6 ohm cm at 20 Celsius. What is its resistance at -20 Celsius?

Question

anonymous · Answer

i think you might need a table

anonymous · Answer

resistance is given by the product of resistivity and length divided by the area of cross section of the wire. change in resistance can be given by the product of original resistance multiplied by thermal coefficient of resistance and the change in temperature.. so in this way you can find the resistance at -20 c.

anonymous · Answer

table for what? BTW, The inferred absolute temp of copper is -234.5 Celsius.

anonymous · Answer

at the very list the thermal coefficients of resistancee of materials.

anonymous · Answer

like aeronik said :D

anonymous · Answer

i tried that a while ago and i got the wrong answer. i'll try again. anyway, thanks! :)

anonymous · Answer

well dont give up :D

anonymous · Answer

i have designed a method from preparation of commercial gases like hydrogen sulphide, steam, ammonia and sulphur dioxide all in one go.. but since i dont have facilities at college i just wanted to open it up here, is that done ?

anonymous · Answer

hey and be careful of your change in temperature it will be -40..

anonymous · Answer

thanks! :)

anonymous · Answer

got the answer now! thank you guys! :)

anonymous · Answer

GOOD :D

anonymous · Answer

:) anyway, i should finish answering all the problems now because will be having a quiz tomorrow. :D Thank you again! :D

anonymous · Answer

study hard :D

anonymous · Answer

welcome...