Question

determine the resistance of a 75 - w lightbulb connected to its proper source voltage of 110 v. express your answer to two significant figures and include the appropriate units.

part b
determine the current through a 75 - w lightbulb connected to its proper source voltage of 110 v. express your answer to two significant figures and include the appropriate units.

Explanation:

Step1: Use the power formula \(P=\frac{V^{2}}{R}\) to find resistance

We know that \(P = 75\space W\) and \(V=110\space V\). Rearranging the formula \(P=\frac{V^{2}}{R}\) for \(R\), we get \(R=\frac{V^{2}}{P}\).
Substitute the values: \(R=\frac{(110)^{2}}{75}\)

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Rounding to two significant figures, \(R = 160\space\Omega\)

Step2: Use the power formula \(P = VI\) to find current

We know that \(P = 75\space W\) and \(V = 110\space V\). Rearranging the formula \(P=VI\) for \(I\), we get \(I=\frac{P}{V}\)
Substitute the values: \(I=\frac{75}{110}\)

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Rounding to two significant figures, \(I=0.68\space A\)

Answer:

For resistance: \(160\space\Omega\)
For current: \(0.68\space A\)