# Textbook: Learning and Questions

Thread Starter

#### anumuthu

Joined Jun 1, 2022
2
Hi, I've started refreshing my knowledge and experience by starting with the textbook provided in AAC website. However, I couldn't post my comments in that particular section of the chapter. For example I've a below question:
Question 10
Determine whether or not the following resistors measure within the resistance range specified by their color codes:
(Grn, Blu, Gld) Measured resistance = 6.73 Ω
Answer: (Grn, Blu, Gld) Measured resistance = 6.73 Ω Out of tolerance!
I couldn't figure out the answer, because for a 5 band resistor the 3rd code is a significant digit.

So my questions are:
1. How do I post me comment in the textbook section?
2. If someone could help me figure out the above question, it would be great.
https://www.allaboutcircuits.com/worksheets/resistors/

Thank you

#### KeithWalker

Joined Jul 10, 2017
2,403
Over the last 90 years or so, there have been quite a few different ways of indicating the value of a resistor using the standard colour codes. When I first got into electronics using second hand components from pre-war (WWII) valve radios, the usual code was "body, tip, spot" with the tolerance on the other end. Then it was modified over the years to a three-band system and more bands have been added since. If you are not sure of the coding, look up "resistor colour codes" and include how many bands it has.

#### dl324

Joined Mar 30, 2015
14,684
Welcome to AAC!
I couldn't figure out the answer, because for a 5 band resistor the 3rd code is a significant digit.
The resistor in question only has 3 bands, so it's a 5.6 ohm resistor with 20% tolerance.

What level of knowledge/experience are you refreshing from?

Thread Starter

#### anumuthu

Joined Jun 1, 2022
2
Welcome to AAC!

The resistor in question only has 3 bands, so it's a 5.6 ohm resistor with 20% tolerance.

What level of knowledge/experience are you refreshing from?
Thank you for your response.
I thought it could be a 3 band resistor with no 4th band, so +/- 20% tolerance, with gold as the 3rd band, so the multiplier is 10^-1. However, since the questions explicitly stated all the color codes mentioned refer to 5 band I was confused.

I have an undergrad degree in engineering( i.e. two decades ago), I've worked as design engineer in automotive and semiconductor industry. I am working on getting back to work force after decade long career break. I am pursuing hardware/electrical design roles.

#### dl324

Joined Mar 30, 2015
14,684
However, since the questions explicitly stated all the color codes mentioned refer to 5 band I was confused.
I read the problem and think it's just poorly worded.