Examkin

Question

Difficulty: EasyResistors and Potentiometers

An electronics technician selects a four-band carbon-film resistor with the color sequence Brown, Green, Red, and Gold. What is the nominal resistance and tolerance of this resistor?

  1. A
    150 Ω with ±5% tolerance150\ \Omega\text{ with } \pm 5\%\text{ tolerance}
  2. 1.5 kΩ with ±5% tolerance1.5\text{ k}\Omega\text{ with } \pm 5\%\text{ tolerance}Answer
  3. C
    1.5 kΩ with ±10% tolerance1.5\text{ k}\Omega\text{ with } \pm 10\%\text{ tolerance}
  4. D
    15 kΩ with ±5% tolerance15\text{ k}\Omega\text{ with } \pm 5\%\text{ tolerance}

Answer

1.5 kΩ with ±5% tolerance1.5\text{ k}\Omega\text{ with } \pm 5\%\text{ tolerance} (1,500 Ω±5%1,500\ \Omega \pm 5\%)
Decoding the four color bands in standard order gives: Brown = 1 (first digit), Green = 5 (second digit), Red = 10210^2 or ×100\times 100 (multiplier), and Gold = ±5%\pm 5\% (tolerance). Calculating 15×100 Ω15 \times 100\ \Omega yields 1,500 Ω1,500\ \Omega, which converts to 1.5 kΩ1.5\text{ k}\Omega with a ±5%\pm 5\% tolerance.

Step-by-Step Solution

1
Identify the first two significant digit color bands.
Brown represents the digit 1, and Green represents the digit 5, forming the number 15.
In a standard four-band resistor, the first two bands establish the base significant figures.
2
Determine the multiplier from the third band.
Red represents a multiplier of 10210^2 (100100).
The third band indicates the power of ten by which the significant digits are multiplied.
3
Calculate the nominal resistance value.
15×100=1,500 Ω=1.5 kΩ15 \times 100 = 1,500\ \Omega = 1.5\text{ k}\Omega.
Multiplying the base digits by the multiplier yields the total nominal resistance.
4
Identify the tolerance from the fourth band.
Gold indicates a tolerance of ±5%\pm 5\%.
The fourth band specifies the acceptable manufacturing variation percentage.

Key Concept

Four-band resistor color code decoding and tolerance identification
Estimated Time:35s
Rate this question

Topics

Resistors and Potentiometers

More questions from this topic