Variable resistor has three terminal s. What is the purpose of terminal in the middle as the current enter the resistor through the first terminal and goes out of the resistor through
![Taiss 5pcs Potentiometers 1K Ohm,Volume Control Potentiometer,6 Pins Split Shaft Rotary Linear Dual Taper Audio B Type Potentiometer with 5pcs Knob: Amazon.com: Industrial & Scientific Taiss 5pcs Potentiometers 1K Ohm,Volume Control Potentiometer,6 Pins Split Shaft Rotary Linear Dual Taper Audio B Type Potentiometer with 5pcs Knob: Amazon.com: Industrial & Scientific](https://m.media-amazon.com/images/I/71BxsjbcdNL._AC_UF894,1000_QL80_.jpg)
Taiss 5pcs Potentiometers 1K Ohm,Volume Control Potentiometer,6 Pins Split Shaft Rotary Linear Dual Taper Audio B Type Potentiometer with 5pcs Knob: Amazon.com: Industrial & Scientific
![4pcs FOR ALPHA Precision RD901F-B10K Potentiometer / Half-bending bent legs Single Potentiometer Handle Length 15mm 3pin 4pcs FOR ALPHA Precision RD901F-B10K Potentiometer / Half-bending bent legs Single Potentiometer Handle Length 15mm 3pin](https://ae01.alicdn.com/kf/H39c401281f0e4af285ed2a3b38a2d7baV.jpg_640x640Q90.jpg_.webp)
4pcs FOR ALPHA Precision RD901F-B10K Potentiometer / Half-bending bent legs Single Potentiometer Handle Length 15mm 3pin
![Applicable to Yamaha kb-290 electronic organ volume potentiometer single row 7-leg vertical A10K A103 - AliExpress Applicable to Yamaha kb-290 electronic organ volume potentiometer single row 7-leg vertical A10K A103 - AliExpress](https://ae01.alicdn.com/kf/S180d032d3cea4fd0b9c784c97a38e4dc1/Applicable-to-Yamaha-kb-290-electronic-organ-volume-potentiometer-single-row-7-leg-vertical-A10K-A103.jpg)
Applicable to Yamaha kb-290 electronic organ volume potentiometer single row 7-leg vertical A10K A103 - AliExpress
![Panel Mount Right Angle 10K Linear Potentiometer w/On-Off Switch [10K Linear w/ Switch] : ID 3395 : $1.50 : Adafruit Industries, Unique & fun DIY electronics and kits Panel Mount Right Angle 10K Linear Potentiometer w/On-Off Switch [10K Linear w/ Switch] : ID 3395 : $1.50 : Adafruit Industries, Unique & fun DIY electronics and kits](https://cdn-shop.adafruit.com/970x728/3395-01.jpg)