9 It is desired to make a 20 2 coil of wire which has a zero

Last updated: 6/2/2023

9 It is desired to make a 20 2 coil of wire which has a zero thermal coefficient of resistance To do this a carbon resistor of resistance R is placed in series with an iron resistor of resistance R The proportions of iron and carbon are so chosen that R R 20 92 for all temperatures near 20 C Find the values of R and R 0 5 10 3 C airon 5 x 10 3 C 1 a carbon comperature with