Question

A carbon resistor has a value of $62 \times 10^3 \Omega$ with a tolerance of $5\%$. Write the colour code for this resistor in sequence.

Answer 1

Hint: Recall that every digit is associated with a colour that it represents as a band on a resistor. This colour code follows the order of Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey and White, with the first two digits being the two significant figures of the resistance value and the third being the multiplier for it. Use this information to arrive at the colour code for the resistor in sequence.

Complete step-by-step answer:
We know that an electric code is employed to indicate the ratings of resistors in terms of their resistance values.
A resistor is usually marked as shown in the figure, with each band having a colour assigned to it.

In general, the resistance of a four-band resistor as shown in the figure would be deciphered to be:
$R = AB \times 10^C \pm X\%$
Starting from the left-hand side let us see what each band signifies:
Band A: Represents the first significant figure of the resistance value.
Band B: Represents the second significant figure of the resistance value.
Band C: Represents the decimal multiplier indicating the number of trailing zeroes, usually used to determine if the resistance is in the scale of $\Omega,\; k\Omega,\; M\Omega,\; G\Omega$ and so on.
Band D: Represents the tolerance value of the resistor in percentage. If there is no band, then by default, it represents a $20\%$ tolerance. The tolerance represents the deviation of the measured resistance from its written value.
Now, the colour code prescribed for the resistors follows the convention as shown in the table.
We are given that the resistance value is $62 \times 10^3 \Omega$ with a tolerance of $5\%$.
We rewrite this as: $62 \times 10^3 \pm 5\%$
We have:
Band A: 6 [Blue]
Band B: 2 [Red]
Band C: $10^3$ [Orange]
Band X: $\pm 5\%$ [Gold]
Therefore, the colour code for the resistor would be Blue, Red, Orange and Gold.

Colour	Significant figures	Multiplier	Tolerance (%)
Black	0	$10^0 =1$	-
Brown	1	$10^1$	±1
Red	2	$10^2$	±2
Orange	3	$10^3$	±0.05
Yellow	4	$10^4$	±0.02
Green	5	$10^5$	±0.5
Blue	6	$10^6$	±0.25
Violet	7	$10^7$	±0.1
Grey	8	$10^8$	±0.01
White	9	$10^9$	-
Gold	-	$10^{-1}$	±5
Silver	-	$10^{-2}$	±10
None	-	-	±20

Note: An easier way to remember the values associated with each colour is by using a mnemonic taking the first letter of every colour in order BBROYGBVGW as: Better Be Right Or Your Great Big Vacation Goes Wrong.