Question

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?

Answer 1

Given:

The lamp draws the current is

`I=0.50\text{ A}`

The voltage supplied by the generator is

`V=120\text{ V}`

The time for which energy converted is

`\begin{gathered} t=5\text{ min} \\ t=5*60\text{ s} \\ t=300\text{ s} \end{gathered}`

Step-by-step explanation:

(a)

The power delivered by the generator is given by

`P=VI`

Plugging all the values in the above equation, we get

`\begin{gathered} P=120\text{ V}*0.50\text{ A} \\ P=60\text{ watt} \end{gathered}`

The power delivered by the generator is

`60\text{ watt}`

(b)

Energy is converted by the electric lamp is given by

`E=Pt`

Plugging all the values in the above relation, we get

`\begin{gathered} E=60\text{ watt}*300\text{ s} \\ E=18000\text{ J} \end{gathered}`

Thus, the electric energy convert by the lamp is

`18000\text{ J}`