Nate Electrical Practice Exam

According to the resistor color code, what is the resistance of a resistor with colors red, green, and black?

1. 25 ohms

2. 250 ohms

3. 360 ohms

4. None of the above

The correct answer is: 25 ohms

To determine the resistance value of a resistor using the color code, we first need to identify the corresponding numerical values for each color. In this case, the colors are red, green, and black. Red corresponds to the number 2, green corresponds to 5, and black corresponds to 0. The first two colors indicate significant figures and the last one indicates the multiplier. Therefore, we can construct the resistance value as follows: 1. The first digit from red gives us 2. 2. The second digit from green gives us 5. 3. The black color indicates a multiplier of 1 (since black stands for 0 in the multiplier, we effectively multiply by 1). Now, we combine these values: - The significant figures are 25 (from 2 and 5). - The multiplier is 10^0, which is 1. So, when we calculate the total resistance, we get: 25 × 1 = 25 ohms. This confirms that the resistance of the resistor with colors red, green, and black is indeed 25 ohms.