Question

a 1500 - w heater is designed to be plugged into a 120 - v outlet. part a what current will flow through the heating coil when the heater is plugged in? express your answer numerically in ampere using three significant figures. part b what is r, the resistance of the heater? express your answer numerically in ohm using three significant figures.

Explanation:

Step1: Recall power - voltage - current formula

The power formula is $P = VI$, where $P$ is power, $V$ is voltage and $I$ is current. We need to solve for $I$. Rearranging the formula gives $I=\frac{P}{V}$.

Step2: Substitute given values

Given $P = 1500\ W$ and $V=120\ V$. Substituting into $I=\frac{P}{V}$, we have $I=\frac{1500}{120}=12.5\ A$.

Step3: Recall Ohm's law for resistance calculation

Ohm's law is $V = IR$, and we can solve for $R$ (resistance) as $R=\frac{V}{I}$. Since we know $V = 120\ V$ and $I = 12.5\ A$ from previous steps.

Step4: Calculate resistance

$R=\frac{120}{12.5}=9.60\ \Omega$.

Answer:

Part A: $I = 12.5\ A$
Part B: $R = 9.60\ \Omega$