Chapter 22, Problem 57A

a.

To determine

Power delivered by generator.

Answer to Problem 57A

  $P=60\text{W}$

Explanation of Solution

Given:

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

Current through the lamp, $I=0.5\text{A}$

Formula used:

The power is given as,

  $P=VI$

Where, $V$ is voltage across the load and $I$ is current through the load.

Calculation:

On substituting the given valuesin above relation the power delivered is,

  $\begin{array}{l}P=120\times 0.5\\ =60\text{W}\end{array}$

Conclusion:

Therefore, the power delivered is $P=60\text{W}$ .

b.

To determine

Energy transformed.

Answer to Problem 57A

  $E=18\text{kJ}$

Explanation of Solution

Given:

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

Current through the bulb, $I=0.5\text{A}$

Time, $t=5\text{min}=300\text{s}$

Formula used:

The energy power relation is,

  $E=Pt$

Where, $E$ is energy, $P$ is power and $t$ is time.

Calculation:

As, $P=60\text{W}$ from previous subpart.

So, on substituting the values the energy transformed is

  $\begin{array}{c}E=60\times 300\\ =18\text{kJ}\end{array}$

Conclusion:

Therefore, the energy transformed by bulb is $E=18\text{kJ}$ .