A) \[3\times {{10}^{8}}m/s\]
B) \[2\times {{10}^{8}}m/s\]
C) \[1.5\times {{10}^{8}}m/s\]
D) \[6\times {{10}^{8}}m/s\]
Correct Answer: C
Solution :
Here: Critical angle\[C=30{}^\circ \] Now, from the law of total internal reflection, we have \[\sin C=\frac{\upsilon }{c}\] Or \[\sin 30{}^\circ =\frac{\upsilon }{3\times {{10}^{8}}}\] \[\upsilon =\frac{1}{2}\times 3\times {{10}^{8}}\] \[=1.5\times {{10}^{8}}m/s\]You need to login to perform this action.
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