Question

A resistor is marked with colors red, red, orange and gold. Write the value of its resistance.

Verified
128.4k+ views
Hint: The resistance and tolerance of a resistor is marked on the resistor by using the color bands. This color band used is generally known as the resistance color code. To solve this question we use the color code chart of resistance.

We have a resistor with four color bands on it; red, red, orange and gold.
We have to find the resistance of the resistor.
For this we have a resistor color code chart.

 Color Digit Multiplier Tolerance (%) Black 0 100 Brown 1 101 ±1 Red 2 102 ±2 Orange 3 103 Yellow 4 104 Green 5 105 ±0.5 Blue 6 106 ±0.25 Violet 7 107 ±0.1 Grey 8 108 White 9 109 Gold 10-1 ±5 Silver 10-2 ±10 None ±20

Here the first color is ‘red’.
The first color band on the resistor is the first significant digit of resistance
According to the chart, the significant digit for red is = 2
Second color band is the second significant figure of resistance.
Second color here is again red.
We know the significant digit for red is = 2.
The third color band is the decimal multiplier of the first two significant digits.
Third band here is orange.
From the chart, the multiplier value of orange is =${{10}^{3}}$
The fourth band gives the tolerance of the resistance.
Fourth band given here is gold.
Tolerance of gold =$\pm 5%$
Therefore, the resistance value of the resistor with color code red, red, orange, gold is
$22\times {{10}^{3}}\pm 5%\Omega$ .

Note:
Resistance is the property of an electric component to resist the flow of current. Resistance in a circuit can be defined as the ratio of voltage applied to the current flowing through the circuit. Unit of resistance is ohms$\left( \Omega \right)$.
A resistor limits the flow of electric current in an electric circuit.