What should be the cross-sectional area of a nickel wire for the manufacture

What should be the cross-sectional area of a nickel wire for the manufacture of a rheostat designed for a resistance of 10 ohms with a wire length of 4 m?

To find out the required cross-section of the nickelin wire used, we will use the formula: R = ρн * l / S, from where we can express: S = ρн * l / R.

Const: ρн – beats. electrical resistance (approx. ρн = 0.4 Ohm * mm2 / m).

Data: l – wire length (l = 4 m); R – required resistance (R = 10 Ohm);.

Let’s make a calculation: S = ρн * l / R = 0.4 * 4/10 = 0.16 mm2.

Answer: The nickel wire used must have a cross section of 0.16 mm2.