Wednesday, June 4

ANSWERS!!
Grade 12 Electric Circuits: Resistivity Problems

1) A = ρL/R
= (1.7 x 10^-8)(20) / (0.10)
= 3.4 x 10^-6 m²

A = πr²
r = √(A/π)
= √(3.4 x 10^-6 / π) x 2
d = 2.1 x 10^-3 m

2) L = RA/ρ
= (1.5)(2.5 x 10^-7) / (100 x 10^-8)
= 0.38 m

3) ρ = RA/L
= (0.04)(2.0 x 10^-6 / (5.0)
= 1.6 x 10^-8 Ωm

4) L = RA/ρ
= (3.0)(1.5 x 10^-6) / (100 x 10^-8)
= 4.5 m

5) A = ρL/R
= (5.5 x 10^-8)(0.2) / (0.10)
= 1.1 x 10^-7 m²

A = πr²
r = √(A/π)
= √(1.1 x 10^-7 m² / π) x 2
d = 3.7 x 10^-4 m

Today we corrected Chapter 23: Study Guide Simple Circuits. We were handed Chapter 34: Electric Current (the “fun” thing) and corrected the first page. Lastly, we were given worksheets called Series and Parallel Circuits, and Simple Circuits.