Question

The luminous intensity of a $100$ W unidirectional bulb is $100$ candela. The total luminous flux emitted from the bulb will be

• A. $100\pi$
• B. $200\pi$
• C. $300\pi$
• D. $400\pi$

Answer 1

The correct option is D $400\pi$

We have total luminous flux,
$L=4\pi I=4\pi \times 100=400\pi$