The problem asks which color code corresponds to a $3.9 k\Omega$ resistor, given the standard resistor color code.

1. Problem Description

The problem asks which color code corresponds to a $3.9 k\Omega$ resistor, given the standard resistor color code.

2. Solution Steps

The resistor color code assigns numerical values to colors as follows:

Black = 0, Brown = 1, Red = 2, Orange = 3, Yellow = 4, Green = 5, Blue = 6, Violet = 7, Grey = 8, White =

9.

For a four-band resistor, the first two bands represent the first two digits of the resistance value, the third band represents the multiplier (power of 10), and the fourth band represents the tolerance.

For a $3.9 k\Omega$ resistor, the first digit is 3, and the second digit is

9. The multiplier is $10^3$ since it is $k\Omega$.

The standard tolerance is gold for 5%.

* First digit 3 corresponds to Orange.

* Second digit 9 corresponds to White.

* The multiplier $10^3$ corresponds to Orange.

* Tolerance is Gold.

Therefore, the color code is Orange, White, Orange, Gold.

This matches none of the provided options. Let's verify the other options.

(a) Red, White, Red, Gold: This corresponds to 2, 9, $10^2$, Gold. The resistance is $2900 \Omega$ = $2.9 k\Omega$.

(b) Red, Green, Orange, Silver: This corresponds to 2, 5, $10^3$, Silver. The resistance is $25000 \Omega$ = $25 k\Omega$.

(c) Orange, Green, Orange, Silver: This corresponds to 3, 5, $10^3$, Silver. The resistance is $35000 \Omega$ = $35 k\Omega$.

(d) Orange, White, Red, Gold: This corresponds to 3, 9, $10^2$, Gold. The resistance is $3900 \Omega$ = $3.9 k\Omega$.

3. Final Answer

The correct answer is (d) orange, white, red, gold.