Correct Answer:
Option C - The luminous flux on the unit area of a surface is called the illuminated density of that surface. Its unit is lumen/m² in M.K.S. It is also called lux. Whereas, CGS unit is fot.
1 fot = 10⁴ lux
C. The luminous flux on the unit area of a surface is called the illuminated density of that surface. Its unit is lumen/m² in M.K.S. It is also called lux. Whereas, CGS unit is fot.
1 fot = 10⁴ lux