NEET2015PhysicsCurrent ElectricityActual
Find the resistance of a hollow cylindrical conductor of length 1.0 mm and 2.0 mm respectively. The resistivity of the material is 2.0 10⁻⁸ m .
Options
- A2.1 10⁻³
- B1.3 10⁻⁴
- C3.2 10⁻⁴
- D4.6 10⁻²
Correct answer
A. 2.1 10⁻³
Step-by-step solution
The area of cross-section of the conductor through which charges will be flow is aligned A & = (20 ~mm )^2- (1.0 ~mm )^2 & =3 mm ^2 aligned The resistance of the wire is therefore aligned R & = 1 A = (2.0 10⁻⁸ ) (10) 3.0 10⁻⁶ & =2.1 10⁻³ aligned