Determine the resistance and length of the nickel wire, the mass of which is 88 grams and the cross-sectional area of 0.5 mm2.

Given:

m = 88 grams = 0.088 kilograms – the mass of nickel wire;

s = 0.5 mm2 – nickel wire cross-section;

r = 0.4 Ohm * mm2 / m is the specific resistance of nickelin;

ro = 8800 kg / m3 – density of nickel.

It is required to determine l (meter) – the length of the nickel wire and its total resistance R (Ohm).

Let’s find the volume occupied by the wire:

V = m / ro = 0.088 / 8800 = 0.00001 m3 = 10000 mm3.

Then the length of the wire will be:

l = V / s = 10000 / 0.5 = 20,000 millimeters = 20 meters.

The total resistance of the wire will be equal to:

R = r * l / s = 0.4 * 20 / 0.5 = 8 / 0.5 = 16 ohms.

Answer: the length of the copper wire will be 20 meters, its total resistance is 16 ohms.