Question

When a 72 W light bulb is connected to a 298 V source, what is the current ?

Answer 1

the current is 0.24 Amperes

Explanation

power is the amount of energy transferred or converted per unit time, it can be found using the formula

$\begin{gathered} P=I*V \\ where\text{ P is the power} \\ I\text{ is the current} \\ V\text{ is the voltage} \end{gathered}$

so

Step 1

a)let

$\begin{gathered} P=\text{ 72 Watts} \\ V=298\text{ V} \end{gathered}$

b) now, replace in the formula and solve for I

$\begin{gathered} P=I*V \\ 72\text{ W=I*298 V} \\ divide\text{ both sides by 298 V} \\ \frac{72W}{298\text{ V}}\text{=}\frac{I*298V}{298\text{ V}} \\ 0.24\text{ Amperes=I} \end{gathered}$

therefore,the current is 0.24 Amperes

I hope this helps you