Tungsten wire has a resistance of 60 ohms. What resistance would this wire have if its cross-sectional

Tungsten wire has a resistance of 60 ohms. What resistance would this wire have if its cross-sectional area was 4 times smaller?

To find the value of the resistance of the taken tungsten wire after reducing the cross-sectional area, we use the ratio: n = Rc / Rn = (ρw * l / Sk) / (ρw * l / Sn) = Sn / Sk, whence we express: Rc = Rn * Sn / Sk.

Variables: Rn – initial resistance of the taken tungsten wire (Rn = 60 Ohm); Sн (initial sectional area) = 4Sк (final area).

Let’s make a calculation: Rк = Rн * Sн / Sk = 60 * 4S / Sk = 240 Ohms.

Answer: The resistance of the taken tungsten wire will increase to 240 ohms.