Lesson: Electrical Conductivity and Resistivity
In this lesson, we will learn how to calculate the electrical resistance of a material given its resistivity, cross-sectional area, and length.
Sample Question Videos
Worksheet: 12 Questions • 3 Videos
Consider two cables, one made of copper and one made of aluminum. Both are 15.00 m long, and the copper cable has a resistance of 0.035 Ω. In determining the electrical and mechanical properties of the cables, use a value of kg/m3 for the density of copper and Ω⋅m for its resistivity. Use a value of kg/m3 for the density of aluminum and Ω⋅m for its resistivity.
What is the weight of the copper cable?
What is the weight of the aluminum cable?
What is the resistance of the aluminum cable?
A wire is drawn through a die, stretching it to double its original length. By what factor is the wire’s resistance increased after stretching?
A rod of pure silicon is used in a particle detector. The rod is 18.0 cm long and has a diameter of 3.00 cm. Find the current through the rod when a potential difference of V is applied across its length. Use a value of Ω⋅m for the resistivity of pure silicon.