a needle is placed 50 cm from the lence forms an image on a sreeen placed 90 cm on either side of the lens determine the focal lengthof convex lens

a needle is placed 50 cm from the lence forms an image on a sreeen pla

1.	a needle is placed 50 cm from the lence forms an image on a sreeen placed 90 cm on either side of the lens determine the focal lengthof convex lens
Answer» ORMULA of LENS FORMULA