Electric Power Practice Test

A 18.0 V battery powers a portable circuit with two resistors in parallel, $R_1=9.0,\Omega$ and $R_2=18.0,\Omega$, giving total resistance $R_\text{eq}=6.0,\Omega$. The total current drawn from the battery is $I=3.0,\text{A}$. Use $P=IV$ to compute the power supplied by the battery. Report power in watts (W). Calculate the power supplied by the battery.

A 9.0 V battery powers a wearable device modeled as two resistors in series: $R_1=3.0,\Omega$ and $R_2=6.0,\Omega$, so the total resistance is $9.0,\Omega$. The same current flows through both resistors and equals $1.0,\text{A}$. Determine the power dissipated by $R_2$ using $P=I^2R$. Give your answer in watts (W). What is the power dissipated by the resistor in the circuit?