advertisement

**PHYS-1500 PHYSICAL MODELING FALL 2006**

A resistor is familiar to most students of high school physics. Its symbol is:

The potential difference (or voltage) across a resistor is proportional to the current passing through it.

*V*

= –

*iR*

, where

*i*

is the current, and

*R*

is the resistance. The minus sign means that the potential decreases in the direction that the current flows.

A capacitor is symbolized by:

The potential difference (or voltage) across a capacitor is proportional to the charge on it.

*V*

= –

*q/C*

, where

*q*

is the charge, and

*C*

is the capacitance. The minus sign means that the potential decreases in passing from the positively charged plate to the negatively charged plate.

An inductor is symbolized by:

The potential difference (or voltage) across an inductor is proportional to the rate of change of current through it.

*V*

*L di dt*

, where

*i*

is the current, and

*L*

is the inductance. The minus sign means that the potential decreases in the direction of increasing current.

A source of emf is often symbolized by:

The longer parallel line indicates the side that is at higher potential (the positive side).