Question

A carbon resistor has following colour code. What is the value of the resistance ?

• A. $6.4\text{M}\Omega \pm 5\%$
• B. $64\text{M}\Omega \pm 10\%$
• C. $530\text{k}\Omega \pm 5\%$
• D. $5.3\text{k}\Omega \pm 5\%$

Answer 1

The correct option is C $530\text{k}\Omega \pm 5\%$

Colour code for carbon resistor

$\begin{array}{cccccccccc}Bl,& Br,& R,& O,& Y,& G,& Blue,& V,& Gr,& W\\ 0& 1& 2& 3& 4& 5& 6& 7& 8& 9\end{array}$

Resistance, $R=AB\times C\pm D$

Bands $A$ and $B$ are the first two significant figure of resistance
$B$ and $C$ indicated the decimal multiplier or the number of zeros that follow $A$ and $B$

$B$ and $D$ is tolerance:

Gold$=\pm 5\%$
Silver$=\pm 10\%$
No colour$=\pm 20\%$

$R=53\times {10}^4\pm 5\%=530\text{k}\Omega \pm 5\%$