The electrical resistivity of tungsten is 0.055 μOhm * m. What is the cross-sectional area of a 10 cm long tungsten wire with an electrical resistance of 100 Ohm?
The resistance of a conductor depends on its parameters. From the cross-sectional area S of the wire, its length. We have, by condition, l = 10 cm = 0.1 m. From the material from which it is made, in our case, a tungsten wire is taken, with a specific electrical resistance of tungsten ρ = 0.055 μOhm • m. R = (ρ • l): S. In this formula, it is necessary to find the cross-sectional area S = (ρ • l): R. since the electrical resistance of the wire is given in the problem statement. R = 100 ohms. S = (0.055 μOhm • m • 0.1 m): 100 Ohm = 0.55 μ (m • m) = 0.55 sq. Mm.
Answer: 0.55 sq. Mm.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.