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

PHYSICS · Single correct · A Level · Physics · Waves · Waves

Problem

In a 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 geometrical centre becomes

75\%

of its previous value. The wavelength of light is

6000\ \text{\AA}

and

\mu_{\text{glass}}=1.5

. The thickness of the film cannot be: (a)

0.2\ \mu\text{m}

(b)

1.0\ \mu\text{m}

(c)

1.4\ \mu\text{m}

(d)

1.6\ \mu\text{m}