Finger prints on a piece of paper may be detected by sprinkling fluorescent
powder on the paper and then looking it into [MP PET/PMT 1988]
Sunlight
Infrared light
Ultraviolet light
Gold number is [MP PET/PMT 1988]
Glycerine has [MP PMT/PET 1988; MP PMT 1989, 91; AIIMS 1997]
Astigmatism (for a human eye) can be removed by using
[CPMT 1972; MP PET/PMT 1988; CBSE PMT 1990]