The value of carbon resistance is 54 × 103 Ω. The percentage tolerance is 5%. What is the colour code sequence of carbon resistance?
Green, Yellow, Orange, Golden bands
Understanding Carbon Resistor Colour Codes
Carbon resistors are common electronic components used to oppose the flow of current. Their resistance value and tolerance are often indicated using a series of coloured bands around the body of the resistor. Each colour corresponds to a numerical value or a multiplier or tolerance percentage.
Decoding the Resistance Value
The given resistance value is \(54 \times 10^3 \, \Omega\). This value can be written as \(54000 \, \Omega\). The tolerance is 5%.
The standard colour code uses four bands:
- Band 1: First significant digit
- Band 2: Second significant digit
- Band 3: Multiplier (power of 10)
- Band 4: Tolerance
Carbon Resistor Colour Code Chart
Here is a table showing the values for each colour:
| Colour | Band 1 (Digit) | Band 2 (Digit) | Band 3 (Multiplier) | Band 4 (Tolerance) |
|---|---|---|---|---|
| Black | 0 | 0 | \(10^0\) (1) | |
| Brown | 1 | 1 | \(10^1\) (10) | ±1% |
| Red | 2 | 2 | \(10^2\) (100) | ±2% |
| Orange | 3 | 3 | \(10^3\) (1k) | |
| Yellow | 4 | 4 | \(10^4\) (10k) | |
| Green | 5 | 5 | \(10^5\) (100k) | ±0.5% |
| Blue | 6 | 6 | \(10^6\) (1M) | ±0.25% |
| Violet | 7 | 7 | \(10^7\) (10M) | ±0.1% |
| Grey | 8 | 8 | \(10^8\) (100M) | ±0.05% |
| White | 9 | 9 | \(10^9\) (1G) | |
| Gold | \(10^{-1}\) (0.1) | ±5% | ||
| Silver | \(10^{-2}\) (0.01) | ±10% |
Applying the Colour Code to \(54 \times 10^3 \, \Omega\)
The resistance is \(54 \times 10^3 \, \Omega\).
- The first digit is 5. Looking at the chart, the colour for 5 is Green. This is the first band.
- The second digit is 4. Looking at the chart, the colour for 4 is Yellow. This is the second band.
- The multiplier is \(10^3\). Looking at the chart, the colour for \(10^3\) is Orange. This is the third band.
- The tolerance is 5%. Looking at the chart, the colour for ±5% is Gold. This is the fourth band.
Therefore, the colour code sequence for a carbon resistor of \(54 \times 10^3 \, \Omega\) with 5% tolerance is Green, Yellow, Orange, Golden bands.
Let's check this sequence against the given options:
- Option 1: Yellow (4), Green (5), Orange (\(10^3\)), Gold (±5%) gives \(45 \times 10^3 \, \Omega\) ±5%. This does not match \(54 \times 10^3 \, \Omega\).
- Option 2: Green (5), Yellow (4), Orange (\(10^3\)), Gold (±5%) gives \(54 \times 10^3 \, \Omega\) ±5%. This matches the given value.
- Option 3: Blue (6), Grey (8), Yellow (\(10^4\)), Silver (±10%) gives \(68 \times 10^4 \, \Omega\) ±10%. This does not match \(54 \times 10^3 \, \Omega\).
- Option 4: Blue (6), Yellow (4), Orange (\(10^3\)), Silver (±10%) gives \(64 \times 10^3 \, \Omega\) ±10%. This does not match \(54 \times 10^3 \, \Omega\).
The colour code sequence Green, Yellow, Orange, Golden bands correctly represents a carbon resistance of \(54 \times 10^3 \, \Omega\) with 5% tolerance.
Important Questions from Resistance and Resistivity
Which of the following metals has the lowest electrical resistivity?
When electric current is passed through a wire, the amount of heat produced in a wire depends upon _______.
I. Length
II. Thickness
A uniform wire of resistance 9Ω is bent in the form of an equilateral triangle. Find the effective resistance across a side of the triangle.
Which of the following relations are wrong?
I. The specific conductance is given by the relation \(k = \frac{1}{R}\left( {l/A} \right)\)
II. The equivalent conducting is given by the relation \(\lambda = \frac{{100\;K}}{C}\)
III. The specific resistance is given by the relation \(\rho = \frac{{Rl}}{A}\)
A current is flowing through a metallic wire. If the wire is heated, which quantities change?
