22_Chapter 17 HomeworkCH17 Current and Resistance

22_Chapter 17 HomeworkCH17 Current and Resistance - 90...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
90 CHAPTER 17 (b) The cost of operating the iron for 20 minutes is () 5 6 1 kWh 8.6 10 J $0.080 kWh $0.019 1.9 cents 3.60 cost E rate =⋅   = =   ×   17.51 Ohm’s law gives the resistance as ( ) RV I = ∆ . From RL A ρ = , the resistivity is given by ( ) RA L . The results of these calculations for each of the three wires are summarized in the table below. ( ) m L ( ) R ( ) m Ω⋅ 0.540 10.4 6 1.41 10 × 1.028 21.1 6 1.50 10 × 1.543 31.8 6 1.50 10 × The average value found for the resistivity is 6 av 1.47
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

This document was uploaded on 10/20/2011.

Ask a homework question - tutors are online