In YDSE, both slits produce equal intensities on the screen. A transparent thin film…

PHYSICS · Single correct · AP · Physics 2: Algebra-based · Waves Sound and Physical Optics · Waves Sound and Physical Optics

Problem

In YDSE, both slits produce equal intensities on the screen. A

100\%

transparent thin film is placed in front of one slit. The intensity at the centre becomes

75\%

of the previous intensity. The wavelength of light is

6000\,\text{\AA}

and the refractive index of glass is

1.5

. The minimum thickness of the glass slab is (1)

0.2\,\mu\text{m}

(2)

0.3\,\mu\text{m}

(3)

0.4\,\mu\text{m}

(4)

0.5\,\mu\text{m}