---
title: "Active/passive components and color code"
subject: "Basic Electronics Engineering"
chapter: 1
key: "semester_2/basic_electronics_engineering:active-passive-color-code"
source: https://www.bctengineer.com/q/semester_2/basic_electronics_engineering/active-passive-color-code
site: BCT Engineering
---

# Active/passive components and color code

Basic Electronics Engineering · Chapter 1: Basic Circuits Concepts

- Asked in: 2071 Bhadra, 2+2 marks
- Video: [Active And Passive Components | Basic Electronics Components](https://www.youtube.com/watch?v=pNTVTV6QohQ) — Instrumentation Hub
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_2/basic_electronics_engineering/active-passive-color-code
- Whole chapter: https://www.bctengineer.com/md/semester_2/basic_electronics_engineering/chapter-1

## Question

Define active and passive circuit component. Determine the color code of the following resistor 75 KΩ ± 10%.

## Short answer

Active components supply energy or amplify (e.g., transistor); passive components cannot amplify (e.g., resistor). The colour code for 75 kΩ ±10% is Violet (7), Green (5), Orange (×10³), Silver (±10%).

## Answer

#### Active circuit component
A component that supplies energy to the circuit or controls the flow of current/amplifies a signal using an external power source. Examples: transistor, op-amp, SCR, IC.

#### Passive circuit component
A component that can only store, absorb or dissipate energy and cannot amplify or generate power. Examples: resistor, capacitor, inductor.

#### Colour code of 75 kΩ ± 10%
75 kΩ = 75 × 10³ Ω → digits 7 and 5, multiplier ×10³.

| Band | Colour | Meaning |
|---|---|---|
| 1st | Violet | 7 |
| 2nd | Green | 5 |
| 3rd (multiplier) | Orange | ×10³ |
| 4th (tolerance) | Silver | ±10% |

**Answer: Violet, Green, Orange, Silver**

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Which group contains only passive components?
   A. Resistor, capacitor, inductor
   B. Transistor, op-amp, SCR
   C. Resistor, transistor, IC
   D. Battery, capacitor, op-amp
   Answer: A. Resistors, capacitors and inductors only store, absorb or dissipate energy. (Key point: Passive component)

2. For 75 kΩ, which colours give the digits 7 and 5?
   A. Violet, Green
   B. Blue, Yellow
   C. Violet, Orange
   D. Green, Violet
   Answer: A. Violet = 7, Green = 5. (Key point: Digit bands for 75 kΩ)

3. 75 kΩ = 75 × 10³ Ω. Which colour is the multiplier band?
   A. Red
   B. Orange
   C. Yellow
   D. Green
   Answer: B. Orange stands for ×10³. (Key point: Multiplier)

## Related in Basic Electronics Engineering

- [Active and passive components, transconductance](https://www.bctengineer.com/question.md?key=semester_2%2Fbasic_electronics_engineering%3Aactive-passive-component) — Basic Electronics Engineering, chapter 1
- [Resistor value from colour code](https://www.bctengineer.com/question.md?key=semester_2%2Fbasic_electronics_engineering%3Aresistor-color-code-value) — Basic Electronics Engineering, chapter 1
- [Thevenin: 4 kΩ resistor, 12 V, 10 mA](https://www.bctengineer.com/question.md?key=semester_2%2Fbasic_electronics_engineering%3Athevenin-12v-10ma) — Basic Electronics Engineering, chapter 1, asked 2×

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