The total power rating of a circuit with 12 volts across R1 of 6 ohms and R2 of 3 ohms is:

To determine the total power rating of a circuit with the given resistances and voltage, it is essential to calculate the total current flowing through the circuit and then use that to find the power.

First, in a simple series circuit, the total resistance (R_total) is the sum of the individual resistances. In this scenario, R1 is 6 ohms and R2 is 3 ohms. Therefore, the total resistance is calculated as:

R_total = R1 + R2 = 6 ohms + 3 ohms = 9 ohms.

Next, using Ohm's Law, which states that voltage (V) equals current (I) times resistance (R), the current can be determined by rearranging the equation to solve for current:

I = V / R_total.

Substituting the values we have:

I = 12 volts / 9 ohms = 1.33 A (approximately).

Now, to calculate the total power (P), we can use the formula:

P = V * I.

Since we are finding the power across the entire circuit, we can also use the formula incorporating resistance:

P = I^2 * R_total.

Using the calculated current:

P = (1.