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Concepts Of Physics MCQ Edition [Volume 1]

Exam: Concepts Of Physics MCQ Edition [Volume 1]
Subject: Physics
Chapter: Photometry

Concepts Of Physics MCQ Edition [Volume 1] · Physics · Photometry

Calculate the radiant flux of a source if it emits 45 joules of...

Calculate the radiant flux of a source if it emits

45

joules of energy over a period of

15 \text{ s}

.

Options

A $0.33 \text{ W}$
B $675 \text{ W}$
C $3 \text{ W}$
D $30 \text{ W}$

Correct answer

C. $3 \text{ W}$

Step-by-step solution

Radiant flux is defined as the total radiant energy emitted per unit time.

\Phi = \dfrac{E}{t}

Given

E = 45 \text{ J}

and

t = 15 \text{ s}

.

\Phi = \dfrac{45}{15} = 3 \text{ W}

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