Question

In Young's double slit experiment, blue-green light of wavelength 500 nm is used. The slits are 1.20 mm apart, and the viewing screen is 5.40 m away from the slits. The fringe width is:

• A. 2.25 x ${10}^{-3}m$
• B. 2.25 x ${10}^{-2}m$
• C. 2.25 x ${10}^{-1}m$
• D. 2.25 x ${10}^{-4}m$

Answer 1

The correct option is A 2.25 x ${10}^{-3}m$

Fringe width $\left(\beta \right)=\frac{D\lambda }{d}$$=\frac{5.4\times 500\times {10}^{-9}}{1.2\times {10}^{-3}}$$=22.5\times {10}^{-4}$$=2.25\times {10}^{-3}m$