Light of wavelength `lambda` is incident on a slit. First minima of the diffraction pattern is found to lie at a distance of 6 mm from the central maximum on a screen placed at a distance of 2 m from the slit. If slit width is 0.2 mm, then wavelength of the light used will be :

Options

A. 4000A
B. 6000A
C. 7000A
D. 7400A

Answer

B