What is Voltage?, What is Current?, What is Power?
When we connect a device in to the circuit we must understand the Voltage, Current and Power issues related to the circuit and device. We must not connect a 1/4 watt resistance in 2volt 1Amp circuit. To understand those pleas go through till end of the article.
From the above figure you can realize the idea of Voltage and Current compared with flow of water with respect to its Hight.
Voltage
- Voltage is the pressure from an electrical circuit’s power source that pushes charged electrons (current) through a conducting circuit, enabling them to do work such as rotating a fan. ( voltage = pressure). Voltage is denoted as V. And the unit is the Volt, V
- Voltage is analogous to pressor, caused by the difference of Hight of water level in Tank-A and Tank-B.
- If we increase Hight of water level, Presser in the pipe increase. Such a way Increase in Potential difference, Voltage will be increased.
Current
- Current is a flow of electrical charge carriers, usually electrons The symbol for current is denoted as I. And the unit is the ampere, A
- Water flows as there ware difference in water level. Similarly Current can only flow between two points, if there are difference on Potential between them.
- A 6Volt battery means difference between two terminal of the battery is 6 Volt. A battery of 12 volt provide higher instant current then 6 volt. (But the continuous flow of current depends on the Storage capacity of Battery)
POWER:
Power (P) is The product of Voltage (V) and Current (I) and the unit is watt. (P=V x I)
Suppose a device (resistance) have to handle voltage drop of 2 volt with maximum current limit 1 amp. Then the power dissipation of the circuit will be 2 x 1 = 2 watt. Here we cannot use a 1/4 W, or 1/2 W, or 1W resistance, we have to use a device with twice the maximum limit. Here we have to use a resistance of 4W.