eli5: how/why does water on a touchscreen have the same effect on it as a finger

Question

eli5: how/why does water on a touchscreen have the same effect on it as a finger

In: 8

Answer 1

Water on a touchscreen has the same effect as a finger because it can conduct electricity. When you touch the screen with your finger, the electrical current in your body flows through your finger and into the screen. This changes the electric field on the surface of the screen, which the touchscreen uses to register where you are touching it.

Water is also a conductor of electricity, so when you touch the screen with water on your finger, the same thing happens. The water conducts the electrical current from your body into the screen, changing the electric field on the surface of the screen and causing it to register your touch.