Draper law

Dra·per law

(drā'pĕr),
a chemical change is produced in a photochemical substance only by those light rays that are absorbed by that substance.
[John William Draper]

Dra·per law

(drā'pĕr law)
A chemical change is produced in a photochemical substance only by those light rays that are absorbed by that substance.
[John William Draper]

Draper,

John W., English chemist, 1811-1882.
Draper law - a chemical change is produced in a photochemical substance only by those light rays that are absorbed by that substance.