4 2 electricity review

Electricity

ELECTRIC CURRENT-The flow of charges.

Charges flow from the positive terminal to the negative terminal.

There must be intermediary path for the charges (conductors).

There must be potential difference between two points. This will literally push the charges from one terminal to another. The greater the potential, the greater the push.

ELECTRIC CURRENT

I= Q/tI=current (A/ampere)Q=charge (C/coulomb)t=time interval (s/second)

CURRENT

I= V/RI=current (A/ampere)V=voltage (V/volts)R=resistance (Ω/ohms)

OHM’S LAW (Current)

VOLTAGE- electrical potential difference, electric tension or electric pressure

RESISTANCE- property of a conductor due to which it opposes the flow of current through it.

I= V/RI=current (A/ampere)V=voltage (V/volts)R=resistance (Ω/ohms)

According to ohm’s law, the resistance of a metallic conductor depends on the following:

1. Length of the conducting wire- the longer the wire, the higher its resistance.

2. Cross-sectional area of the conductor- the thicker the conductor, the lower the resistance.

3. Nature of the conductor- the more free electrons there are, the lower the resistance.

Resistivity

R=ρL/AR=resistance (Ω/ohms)ρ=resistivity of the conductor (Ω·m / ohm-meter)

L=length of the wire (m)A= cross sectional area (m2)

RESISTANCE

Electric Circuit

RATE OF DOING WORKTHE CONVERSION OF ELECTRICAL

ENERGY INTO OTHER FORMS LIKE HEAT ENERGY, CHEMICAL ENERGY, MECHANICAL ENERGY, OR LIGHT ENERGY

POWER

P=QV/tP=IV

P=I2 RP=V2 /R

P=power (W/Watts)Q= Charge(C/Coulomb)V=voltage (V/volts)T= time interval (s/seconds)I=current (A/ampere)R=resistance (Ω/ohms)

POWER

Electric Circuit Series CircuitParallel CircuitCombined Circuit

Series Circuit

Parallel Circuit