Differences

This shows you the differences between two versions of the page.

--- 184_notes:resistivity [2021/02/24 17:45] – bartonmo
+++ 184_notes:resistivity [2021/02/27 04:07] (current) – [Making sense of $R$ ] bartonmo
@@ Line 56: / Line 56: @@
 Why does the bottom fraction make sense? A longer, thinner wire should be more resistive, so the geometric properties make sense (directly proportionally to  $L$  and inversely proportional to  $A$ ). A wire with higher conductivity should be less resistive, which also make sense (inversely proprtional to  $\sigma$ ).
-Resistance has units of volts per amp, which is also called an ohm. An ohm is represented by a capital omega ( $\Omega$ ). Sometimes you may see resistance rewritten in terms of **resistivity**( $\rho$ ), which is simply the inverse of conductivity  $\rho=1/\sigma$ . So using resistivity,  $R=\frac{\rho L}{A}$  - either version of resistance is fine.
+**Resistance has units of volts per amp, which is also called an ohm.** An ohm is represented by a capital omega ( $\Omega$ ). Sometimes you may see resistance rewritten in terms of **resistivity**( $\rho$ ), which is simply the inverse of conductivity  $\rho=1/\sigma$ . So using resistivity,  $R=\frac{\rho L}{A}$  - either version of resistance is fine.
 ==== Ohm's Model ====