A resistor is wired to a battery in a circuit and dissipates a power P1 as heat. A second resistor, with the same resistance, is added in series with the first resistor, leading the circuit (i.e. both resistors) to dissipate a power P2 as heat. How much does the circuit dissipate with two resistors, relative the circuit with one resistor, or in other words, what is the ratio P2/P1?

A resistor is wired to a battery in a circuit and dissipates a power P1 as heat. A second resistor, with the same resistance, is added in series with the first resistor, leading the circuit (i.e. both resistors) to dissipate a power P2 as heat. How much does the circuit dissipate with two resistors, relative the circuit with one resistor, or in other words, what is the ratio P2/P1?