A) \[3\times {{10}^{8}}\,m/s\]
B) \[1.5\times {{10}^{8}}\,m/s\]
C) \[6\times {{10}^{8}}\,m/s\]
D) \[\sqrt{3}\,\times {{10}^{8}}\,m/s\]
Correct Answer: B
Solution :
Refractive index medium\[\mu =\frac{1}{\sin C}\] where \[C\] is critical angle. Given, \[C={{30}^{o}}\] \[\therefore \] \[\mu =\frac{1}{\sin {{30}^{o}}}=\frac{1}{1/2}=2\] From Snells law \[\mu =\frac{{{v}_{0}}}{{{v}_{m}}}\] where \[{{v}_{0}}\] is speed of light in vacuum and\[{{v}_{m}}\] the velocity in medium. \[\therefore \] \[{{v}_{m}}=\frac{3\times {{10}^{8}}}{2}=1.5\times {{10}^{8}}\,\,m/s\]
You need to login to perform this action.
You will be redirected in
3 sec
