Motorcycle Repair: electrical question, narrow gap, wonderful christmas

Question
Hello Mark, haven't used this site in awhile, hope your holidays have been great. can you tell me what the purpose of resistors and relays are used for? Thanks

Answer
Hi Jack,

How's the KZ1000P's?

Hope you hade a wonderful Christmas.

Resistors:
Imagine water flowing through a pipe. If we make the pipe narrow then this will restrict the flow of water. If we force the water (current) through the narrow gap by increasing the pressure (voltage) then energy will be given off as heat. In addition, there will be a significant difference in pressure (voltage) above and below the restriction.
In electronics we use a resistor when we need to reduce the voltage applied to a circuit.

Relays:
Why do I want to use a relay and do I really need to? Anytime you want to switch a device which draws more current than is provided by an output of a switch or component you'll need to use a relay.

Respectfully,
Mark Shively