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...
You can calculate a materials resistance using its resistivity and dimensions. For a simple wire, the formula is R = p*l/A, where p is resistivity, l is length, and A is area (cross sectional. Imagine cutting the wire, you'd see a circular cross section).
Some materials like copper have very low resistance.
Some materials like oil have a very high resistance.
Some materials like carbon have a resistance somewhere in between, but generally fairly high.
Resistors use a strip of carbon to make a high resistance path.
Resistance in a switch is typically minimized by design, so introducing a switch or button should not introduce a lot of resistance. It is tyically better not to use switches of this type in signal critical or high power applications (e.g. sound or battery charging), but charging up a small capacitor or powering a small dc circuit should be fine
To measure resistance, one can use a multimeter. This makes use of Ohm's law. Ohms law shows that
V=I*R
Where V is voltage, R is resistance, and I is current. When a small voltage is applied across your component, the current is measured. Then using the current and voltage, it can figure out what the resistance is. It shows it to you on a display so all you have to do is touch the probe tips to the two legs of the switch.
For a switch this will typically be less than 1 ohm. If you buy from a reputable distributor (e.g. digikey, mouser, arrow, farnell, even LCSC) you can get the "datasheet" and look for the constact resistance. This might be a bit harder with ebay/amazon/aliexpress parts, so just stick with a multimeter.
A cheap handheld one is fine, but I'd say prob look for an EEVBlog or other video looking at good cheap meters; you can get pretty good stuff without breaking the bank. Don't stress over it though; any multimeter is better than no multimeter
What creates resistance in a circuit?
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...