Question

The refractive index of glass with respect to water is $\frac{9}{8}$ . If the velocity and wavelength of light in water are $2.25\times {10}^8$ m/s and 5400Å respectively. Then the velocity and wavelength of light in glass is :

• A. $3\times {10}^{8}m/s;4800A^{\circ }$
  
• B. $2.0\times {10}^{8}m/s;4800A^{\circ }$
• C. $2\times {10}^{8}m/s;2400A^{\circ }$
• D. $3\times {10}^{8}m/s;2400A^{\circ }$

Answer 1

Answer: (B)

$2.0\times {10}^{8}m/s;4800A^{\circ }$

Velocity of light in glass $=\frac{v}{\mu }$$=\frac{2.25\times {10}^8}{\frac{9}{8}}$$=2\times {10}^{8}m/s$

Wavelength of light in glass $=\frac{\lambda }{\mu }$$=4800A^{\circ }$