# How do you find the resistance of a component?

## How do you find the resistance of a component?

Calculating resistance

1. To find the resistance of a component, you need to measure:
2. The resistance is the ratio of potential difference to current.
3. For example, 3 A flows through a 240 V lamp.
4. resistance = 240 ÷ 3 = 80 Ω
5. If you plot a graph of current against potential difference for a wire, you get a straight line.

## How do you measure for resistance in an electrical circuit or component?

To measure resistance:

1. Turn power to circuit OFF.
2. Turn digital multimeter dial to resistance, or ohms, which often shares a spot on the dial with one or more other test/measurement modes (continuity, capacitance or diode; see illustration below).
3. First insert the black test lead into the COM jack.

How do you measure the resistance of two resistors?

Because the two resistors are in series, you know that the same current flows through both. Measure the voltage drop across the new resistor, then use Ohm’s law to calculate the current.

How to calculate meter compensating resistors in Excel?

9.26/.00005 will result in a total series resistance of 185,200 ohms. Subtract the resistance 182,500 from the calculated total resistance of 185,200 and you will get 2700 ohms which will be the internal resistance of the meter movement. Section 2Ammeters

### How to calculate resistance from power and voltage?

Find resistance from power and voltage. 1 P = VI 2 Rearrange Ohm’s Law in terms of I: I = V / R. 3 Substitute V / R for I in the power formula: P = V (V/R) = V 2 /R. 4 Rearrange to solve for resistance: R = V 2 /P. 5 In a parallel circuit, the voltage across one branch is the same as the total voltage. This is not true for a series… More

### How to calculate the resistance of an ammeter?

Suppose you set up a voltage and select a resistor to limit the current to within range of the ammeter. Then the estimate of the ammeter’s resistance is: R METER = V SET I MEASURED − R LIMIT Take note that R METER is usually quite small when compared to typical values of R LIMIT.