Inspired by chotu bot model.
So started to explore circuit designing. @Ashish_Pardeshi sir suggested to start with basic design of circuit for glowing small led light and also to find value of each component with drawing circuit on paper.
Breadboard - 80₹
9V battery - 30₹
Resistance - 2₹
LED - 2₹
Battery cap - 5₹
So, their are two methods 2 find resistance value ohm’s law and krichoff law.
Let’s discuss this to improve basic foundation related to circuit. @Farhan@ravi312@jtd@GN@ARYAN32
Your reasoning looks okay, but not your calculations.
The forward voltage drop of the LED is (assume) 2 V.
Any voltage source you use to light it up will have to be at least 2 V or more. Nothing will happen if your source is, for example, 1 V. Also, ALL voltage sources have some amount of internal impedance, so ideally, you need something a little bit more than 2 V to light up a 2 V LED.
With that, the voltage that needs to be “dropped” by the “current limiting resistor” needs to be
(Voltage of Source)-(FWD Voltage drop of LED)/Current.
So, at 9 V supply, and 2V drop across LED with 20 mA current flow, you get
=(9-2)*1000/20
=7000/20
= 350 ohms
