Question

A carbon resistance with color band is $200\Omega$. If the red band is replaced by a green band then $R$ is

• A. $500\Omega$
• B. $300\Omega$
• C. $400\Omega$
• D. $100\Omega$

Answer 1

The correct option is A

$500\Omega$

Step 1. Given data:

The carbon resistance, $R=200\Omega$

Step 2. Formula used:

As carbon resistors are defined by the colour codes.

The resistor colour code,

$$\begin{gathered} RED\to 2 \\ GREEN\to 5 \end{gathered}$$

Step 3. Finding the new resistance:

As, The carbon resistance, $R=200\Omega$

$R=200\Omega$ has $RED$ colour because $2$ defines $RED$.

If $RED$ is replaced by $GREEN$, then resistance is,

$R=500\Omega$, as $GREEN$ is defined by $5$.

So, the new resistance is,

$R=500\Omega$

Hence, ' option (A) is correct.