I watched so many youtube videos about electronics but i cant seem to understand what is voltage and current. If I = V/R, then in a series circuit, if the voltage is reducing after each component, then the current should also decrease right? I don’t understand the water pipe analogy
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>If I = V/R, then in a series circuit, if the voltage is reducing after each component, then the current should also decrease right?
Not exactly. Voltage difference in electric potential and you need to measure it over the component. You can’t measure it to the ground or some other place. Ground what we define as 0 volts.
So the relevant voltage is the one you get if you measure with a voltmeter and put the probes on the two wires of the resistor. It is not the voltage between one of the wires and the ground.
I would say the water analogy have some problem. Some chase is better to compare to gravitational potential energy. Potential energy = mass * gravitational acceleration * height. Close to the surface of Earth, you can look at the elevation as the gravitational potential difference from what we define as zero elevation
If you drop a ball from the ceiling it will hit the floor at the same speed on the ground floor as it does on the first floor or in the basement. It does not matter where you are relative to the ground the house stands on it only matters how much the elevation changes
If you, on the other hand, drop the ball from the ceiling of the first floor to the floor of the ground floor it will gain 2x the kinetic energy because the gravitational potential difference is 2x higher. From the ceiling of the first floor to the basement is 3x the elevation and 3x the kinetic energy.
If you do it on the 3 top floors of a skyscraper the result is exactly the same. It do not matter you hare high above the ground, it is the elevation difference that matters
This assumes 0-floor thickness and that every room has the same ceiling height. It ignores air resistance. It also assumes the gravitation field is the same, it technically changes with elevation but it is a minuscule effect for short distances.
That you define 0 elevations as the ground does not matter is the difference that is relevant. I
Putting components in series is like splitting up the high something can drop.
There is a current reduction but it happening at the moment you add multiple components in series because the voltage drop is split over them, this means less voltage drop per component and lower current
If you have 20 V source and 2-ohm resistors. If you connect a single one you have 20V voltage drop over it and the current is 20/2= 10 amp.
If you connect two in series the voltage drop over each is 10V. The current is 10/2 = 5 amp.
You can also look at the whole circuit where the two resistors in series are added together and you have 4-ohm resistance. There is not a 20V voltage drop over 4 ohms and the current is 20/4=5 amp
You only have the voltage split up even if the restore has the same value. If you have a 3 and a 5-ohm resistor the voltage drop over them is not equal. The total resistance is 3+5= 8 ohms so the current is 20/8= 2.5 amp.
You can now calulate the voltage drop I=V/R => V=I * R This mean the voltage drop are 2.5 *3 =7.5V and 5 * 2.5 = 12.5V
The water pipe analog is not perfect
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