On illumination...do I have to change the 80 cm to m or something else? Please help

Rose O

New member
solve? A three way bulb has a 665, 1620, 2285 LM in its three settings. Its placed 80 cm above a sheet of paper if an illumination of at least 175 LX is needed on the paper what is the minimum setting the bulb should be set too (as in which of those three settings)?
 
Back
Top