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A 18.0 W LED light bulb is turned on. It has an operating voltage of 120 V.(a)How much current (in A) flows through the bulb? _________:A(b)What is the resistance (in Ω) of the bulb? _________:Ω(c)How much energy (in J) is used each second? _________:J each second

User Abdolence
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1 Answer

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(a)

In order to calculate the current, we can use the formula below:


\begin{gathered} P=I\cdot V\\ \\ 18=I\cdot120\\ \\ I=(18)/(120)=0.15\text{ A} \end{gathered}

(b)

To calculate the resistance, we can use Ohm's Law:


\begin{gathered} R=(V)/(I)\\ \\ R=(120)/(0.15)\\ \\ R=800\text{ ^^^^2126} \end{gathered}

(c)

Since the power of 18 W means 18 J of energy is consumed each second, so the energy used each second is 18 J.

User Rachel Gallen
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