Water Level Indicator circuit using transistors and LEDs Only

#waterlevelindicator
#waterlevelindicatorcircuit
This video is about how a water level indicator circuit works usinv transistors and LEDs only.
This circuit consists of four transistors which acts as switch.The emitter of all transistors are connected to Vcc and bases are use as water level sensors in the tank.The emitters are use to connect LEDs and Buzzer.How this circuit works?
Initially when tank is empty Yellow LED will be ON and indicates that Water tank is empty.When water is pour in the tank and it becomes half then Green LED will be ON.Similarly when is full the Red LED and Buzzer will be ON.
Circuit Components
1.Transistors (4x2N3904)
2.Three LEDs(Yellow,Green,Red)
3.Buzzer
4.Different Resistors
5.Connecting Wires
6.Breadboard
7.Powersupply