I’m planning to add a momentary switch to a single loop DC circuit. Will this cause any amount of resistance in the circuit? I’m a complete noobie when it comes to electronics, any resource links or clarification is appreciated. I know the type of material/width of wire and a pot will cause resistance but will any component put in line with the circuit cause resistance, and if so how do I go about measuring the resistance for each component within the circuit?
That is pretty much exactly a conventional momentary switch. It just happens to be packaged for use controlling something a little different.
It should be fine for your application.
One thing to note - the contacts will probably “bounce” as the switch is closed. Produce a string of momentary connections and disconnections for, oh, say the first few thousandths of a second. That’s perfectly normal for a mechanical switch.
That won’t matter in its intended application. But if you are using it with electronics, say counting the number of times the switch is operated - the results can be unexpected.
You can look up “debounce” to see how this can be worked-around.