In a single slit diffraction experiment,the width of the slit is doubled. Which one of the following statements is correct?

$A$ single slit diffraction pattern is formed with light of wavelength $6384 Å$. The second secondary maximum for this wavelength coincides with the third secondary maximum in the pattern for light of wavelength $\lambda_0$. The value of $\lambda_0$ is (in $Å$)

Which of the following are true for a single slit diffraction?
$(A)$ Width of central maxima increases with increase in wavelength keeping slit width constant.
$(B)$ Width of central maxima increases with decrease in wavelength keeping slit width constant.
$(C)$ Width of central maxima increases with decrease in slit width at constant wavelength.
$(D)$ Width of central maxima increases with increase in slit width at constant wavelength.
$(E)$ Brightness of central maxima increases for decrease in wavelength at constant slit width.

Why does a $DVD$ store almost $30$ times more information than a $CD$?

Define diffraction.

In a diffraction pattern due to a single slit of width $a$,the first minimum is observed at an angle $30^{\circ}$ when light of wavelength $5000 \; \mathring{A}$ is incident on the slit. The first secondary maximum is observed at an angle of