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2 years ago

9

.A 100.0-W lightbulb is 22 percent efficient. This means that 22 percent of the electrical energy is transformed to radiant ener

gy.
a. How many joules does the lightbulb transform into radiant energy each minute it is in operation?

b. How many joules of thermal energy does the lightbulb output each minute?

1 answer:

algol [13]2 years ago

6 0

Answer:

Explanation:

100 W bulb is using energy of 100 J in one second.

22 percent of the electrical energy is transformed to radiant energy.

a )

So , electrical energy is transformed to radiant energy per second

= 100 x .22 = 22 J

energy transformed in one minute = 22 x 60 J

= 1320 J

b )

electrical energy is transformed to heat energy per second

= 100 x .78 = 78 J

energy transformed in one minute = 78 x 60 J

= 4680 J

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