railway DFCCIL Junior Executive 2023 (CBT 1 & CBT 2) Mock Test Utilization of Electrical Energy Illumination
Which of the following statements about the law of illumination is correct?
1
The illumination is directly proportional to the luminous intensity and inversely proportional to the square of distance of the surface from the source.
2
The illumination is directly proportional to the luminous intensity and inversely proportional to the distance of the surface from the source.
3
The illumination is directly proportional to the distance of the surface from the source and inversely proportional to the square of luminous intensity.
4
The illumination is directly proportional to the square luminous intensity and inversely proportional to the distance of the surface from the source.