**Example 1**

### Find the value of a resistor with the following code.

1st band → brown

2nd band → black

3rd band → orange

4th band → silver

Solutions

Solutions

BBROYGBVGW

Black = 0, brown = 1, red = 2, orange = 3, yellow = 4, green = 5, blue = 6, violet = 7, grey = 8, white = 9

Tolerance is

Gold ± 5%, silver ± 10%, no band/colour ± 20%

If the colour bands are brown, black and orange

Brown – 1

Black – 0

Orange – 3 ( i.e 3 zeros)

I.e 10 with 3 zeros or 10,000Ω

Question: HOW COME? 🤔

## Ans: The third band indicate the number of zeros we’ll be having)

10,000Ω resistor with silver forth band, it’s value and tolerance will be 10,000 ohms plus or minus 10%

Question: HOW COME? 🤔

#### And: why is because silver represent 10%)

20% of 10,000 = 10/100 × 10000

= 1000Ω[ohms]

Therefore, the resistor will have a value of 10,000 ± 1000

I.e 10,000+1000 or 10,000 – 1000 = 11,000Ω or 9,000Ω. ( 3 marks)

## Example 2

#### Find the value of a resistor with the following color code.

1st band – brown

2nd band – red

3rd band – yellow

4th band – gold

Solutions

Brown = 1, red = 2, yellow = 4 (i.e 4 zeros), gold = 5%

The resistor is 120,000Ω

The resistor value for 120,000Ω of gold 4th band is;

120,000 × 5/100 = 6000Ω

Therefore, the resistor will have a value of 120,000 ± 6000

I.e 120,000 + 6000 = 126,000Ω

120,000 — 6000 = 114,000Ω

= 126,000Ω or 114,000Ω