Chapter 22, Problem 54A

To determine

Rate of transformation of energy by bulb.

Answer to Problem 54A

  $P=144\text{W or 144}\text{J/s}$

Explanation of Solution

Given:

Applied voltage, $V=120\text{V}$

Current produced, $I=1.2\text{A}$

Formula Used:

The electrical power is given as,

  $P=VI$

Where, $P$ is electrical power, $V$ is applied voltage and $I$ is current produced.

Calculation:

Since electrical power is rate of transformation of electrical energy.

So, on substituting the given values in above relation,

  $\begin{array}{c}P=120\times 1.2\\ =144\text{W}\\ \text{=144}\text{J/s}\end{array}$

Conclusion:

Therefore, the rate of transformation of electrical energy by lightbulb is $P=144\text{W or 144}\text{J/s}$ .