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2 years ago

15

A lamp is 15% efficient. How much electrical energy must be supplied to the lamp each second if it produces 30 J of light energy

per second? *WILL MARK BRAINLIEST*

2 answers:

dem82 [27]2 years ago

7 0

200 Joules should be supplied in the circuit.

Efficiency = output/inupt

Here the output is 30J and input is missing

$\sf \dfrac{30}{I} * 100 = 15$

multiplied with 100, to covert it into percentage

$\sf 3000 = 15(I)$

$\sf I = \dfrac{3000 }{15}$

$\sf I = 200J$

sammy [17]2 years ago

7 0

Let that be X

Efficiency is 15% means the lamp produces 15J of light energy when 100J energy applied.

$\\ \rm\Rrightarrow \dfrac{30}{x}(100)=15$

$\\ \rm\Rrightarrow 3000=15x$

$\\ \rm\Rrightarrow x=200J$

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