how voltage affect current - voltage doubling - current doubling, linearly proportional relationship
how resistance affect current - resistance doubling reduces current to half, inversely proportional
ohms law formula - I = V / R
The Ohm`s Law:
“For a constant resistance , if the voltage in circuit is increased, more current will flow, and if the voltage is decreased, less current will flow. Also, for a constant voltage, if the resistance in circuit is increased, less current will flow, and if the resistance is decreased, more current will flow.”
kilo - thousand
mega - million
mili - one thousand
micro - one million
Power is the rate which energy is used. P = E/t E - energy is measured in joules J, power is measured in Watts W. Watt is joule divided by second.
One Watt - is the amount of power when one joule of energy is consumed in one second. The number of joules consumed in 1 second is always equal to the number of watts.
kilowatthour (kWh) - unit of energy. E = P x t. You use 1 kWh of energy when you use 1000 watts of power for one hour. 100W light bulb burning for ten hours uses 1kWh of energy.
P= V x I = V^2 / R
surface = circumference times length
the power raiting - the maximum amount of power that a resistor can dissipate without being damaged by excessive heat buildup.
Kirchhoff's Current Law (KCL) - At any point in an electrical circuit where charge density is not changing in time, the sum of currents flowing towards that point is equal to the sum of currents flowing away from that point.
Kirchhoff's Voltage Law (KVL) - The directed sum of the electrical potential differences around a closed circuit must equal zero.