ELI5: Explain Like I'm 5

Contact resistance

Contact resistance is like a type of resistance that is between two things when you touch them together. It is a bit like when you have a light switch, and you push the switch down to turn the lights on. When you push it down, electricity has to flow from one part of the switch to the other. The contact resistance is the resistance that the electricity has to go through when it flows from one part to the other.
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