resistance

[searley]

well lost with this one can anyone point is in the write direction ?

a copper conductor has a resistivity 1.78x10-8ohms. determine the resistance of 100m of 2.5mm2

thanks for checking this out.

 

[Apache]

1.78X10-6!

 

[Apache]

well lost with this one can anyone point is in the write direction ?a copper conductor has a resistivity 1.78x10-8ohms. determine the resistance of 100m of 2.5mm2

thanks for checking this out.

now if the resistivity was 1.78X10-8ohm/mm2 then you'd have to allow for the csa of the 2.5mm.

As you have written the question you just multiply the resistivity by length!

(I did it in my head )

 

[searley]

the question was 10-8

this is what i can`t work out the csa bit ?

 

[gullyboy_131]

R= pl/a

R= 1.78x10-8 X 100/ 2.5x10-6

R= 0.712ohms

well thats what i make it mate

 

[searley]

top man gullboy that is the answer on me sheet.just did`nt have a clue how to go on with it .

cheers pal.