Light with an energy flux of 22 W cm-2 falls normally on a non-reflecting surface of area 20 cm2. The total amount of energy falling on the surface during a 30 minute time` span will be:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → $7.92 \times 10^5 J$
Total energy falling on the surface is -
E = Energy flux × Area × Time
$=22×20×1800$
$=7.92 \times 10^5 J$