$A$ carrot looks orange in colour because of the $\beta$-carotene molecule in it. This means that the $\beta$-carotene molecule absorbs light of wavelengths

Assertion : Corpuscular theory fails in explaining the velocities of light in air and water.
Reason : According to corpuscular theory,light should travel faster in denser medium than in rarer medium.

Match Column-$1$ with Column-$2$ when a wave propagating in a denser medium enters a rarer medium:

Column-$1$	Column-$2$
$(a)$ Speed	$(i)$ Increases
$(b)$ Its amplitude	$(ii)$ Decreases
	$(iii)$ Remains constant

Two monochromatic (wavelength $\lambda = a/5$) and coherent sources of electromagnetic waves are placed on the $x$-axis at the points $(2a, 0)$ and $(-a, 0)$. $A$ detector moves in a circle of radius $R (R \gg 2a)$ whose center is at the origin. The number of maximas detected during one circular revolution by the detector are

Red light differs from blue light in its

Which statement is correct for a zone plate and a lens?