Bellwork (2/18)

[ none this week – Happy Rodeo Break ]

Electric Circuits I

2/18/14

The Light Bulb

Conductors:

- Filament

- Internal Wire

- Corkscrew Side

- Base Insulators:

- Glass Globe

- Insulating material (between side and base)

Conditions for a Circuit

There must be a closed conducting path that extends from the positive terminal to the negative terminal.

There must be an electric potential difference across the two ends of the circuit.

The Battery

A negative charge will gain potential energy and voltage as it moves from positive terminal to negative terminal in the battery

The Circuit

A negative charge will lose potential energy and voltage as it moves from negative terminal to positive terminal in the circuit

Battery and Circuit

A negative charge has the least amount potential energy at positive terminal

A negative charge has the greatest amount potential energy at negative terminal

Voltage = Potential Difference

High PE

Low PE

Schematic Symbols

• Wires:• Resistor (elec. device):• Switch:• Battery (Outlet):• Fuse: • Connected wires:• Unconnected wires

In your notes define:

• Electric resistance - unit is ohms (Ω)• Electric current - unit is amperes (A)• Electric Power - unit is watts (W)• Voltage source – “… dry cell, battery, outlet

or generator, …” • Circuit• Series circuit• Parallel circuit