Physics 2 M3

Electric Current (I)

is the rate which charge flows

Conventional current

is define to move in the direction of the electric field.

Positive charges

move in the direction of the electric field and same direction as conventional current

Negative charges

move in the direction of opposite to the electric field.

electronic flow

Flow of electron sometimes referred to as

Drift velocity (vd)

is the average speed which charges move

Ohm’s Law

The current that flows through most substances is directly proportional to the voltage (V) applied to it.

Georg Simon Ohm

The German physicist _______ was the first to demonstrate experimentally that the current in a metal wire is directly proportional to the voltage applied:

Resistance

is the electric property that impedes the flow of current.

simple circuit

in which a closed path for current flow is supplied by conductors connecting a load to the terminals of a battery. It has a single source and a single resistor.

Resistivity

( ) is a measure of resistance of a given size of a specific material to electrical conduction

Conductors, Semiconductors and Insulators

The values of resistivity shows that materials falls into three groups:

Temperature coefficient of resistivity

is the measure in electrical resistance of any substance of any substance per degree of temperature change

Electric Power (P)

is the rate that energy is supplied by a source or dissipated by a device

Electrical Energy (E)

is energy release when electric charges flow through any point in an electric circuit.

Power Rating

is the amount of electrical energy it uses per second.

Energy Consumption

is the amount of energy or power used.

Power Efficiency

is defined as the ratio of output power divided by the input power.