A lamp draws 0.50 A from a 120 V generator. (a) How much power does the generator deliver to the lamp? (b)How much electric energy does the lamp convert to light and heat in a period of 5.0 minutes?

Respuesta :

Given:

The lamp draws the current is

[tex]I=0.50\text{ A}[/tex]

The voltage supplied by the generator is

[tex]V=120\text{ V}[/tex]

The time for which energy converted is

[tex]\begin{gathered} t=5\text{ min} \\ t=5\times60\text{ s} \\ t=300\text{ s} \end{gathered}[/tex]

Explanation:

(a)

The power delivered by the generator is given by

[tex]P=VI[/tex]

Plugging all the values in the above equation, we get

[tex]\begin{gathered} P=120\text{ V}\times0.50\text{ A} \\ P=60\text{ watt} \end{gathered}[/tex]

The power delivered by the generator is

[tex]60\text{ watt}[/tex]

(b)

Energy is converted by the electric lamp is given by

[tex]E=Pt[/tex]

Plugging all the values in the above relation, we get

[tex]\begin{gathered} E=60\text{ watt}\times300\text{ s} \\ E=18000\text{ J} \end{gathered}[/tex]

Thus, the electric energy convert by the lamp is

[tex]18000\text{ J}[/tex]