is there a propper way to add resistance to a current in a design?

Question

do you divide the volts by the amps and whatever the conclusion, add the resistor's ohm value and let ohm's law do the rest or is it done another way

Answer 1

Your question is very confusing. Among other things, resistors are used to limit or control the amount of current through a circuit. If you know the required voltage drop across the resistor and the current through the resistor, Ohm's Law tells you to divide the voltage by the current to obtain the resistance in ohms.

Say you have a light emitting diode (LED) that you want to power from a 5 volt power supply. You put a resistor in series with the LED to control the current. The voltage drop across the LED is about 0.7 volts, so the voltage across the resistor will be about 4.3 volts. If you want 20 milliamperes to flow through the LED (and resistor), the required resistance is 4.3 volts divided by 0.020 amperes, or 215 ohms. The nearest standard resistance value is 220 ohms, which is close enough.

Answer 2

Series resistance simply adds to one another and current will be minimized ie 2 eight ohm speakers in series will result in 16 ohms of resistance and half the current of a single speaker.

However for example two eitht ohm speakers in parallel will result in a four ohm result and double the current will result because the resistance is only half of the single eight ohm speaker.

You can also have series/parallel circuits that in the end will produce what ever the desire is, this is likely what you will need to look at to achieve your outcome.

A combination of the example of two series speakers at 16 ohms and another two series speakers also at 16 ohms but hooked in parallel with the first pair.... would in the end produce an 8 ohm resistance, the same resistance as one single speaker.

Of course this is just an example of series vs. parallel vs. series/parallel hookups, your application would be specific, but in ALL cases ohms law will be the golden rule with the exception of inductive and capacitive reactance which is another kettle of fish.

Answer 3

The current will be based on the resistance in the path.
So adding resistor's will affect the current.

Kind of hard to be more specific without seeing a diagram.

Answer 4

your question isn't very clear. can you restate it, specifying exactly what you want to accomplish?