The time required for the light to go from A to B, when a ray of lilght goes from point A in a medium where the speed of light is `v_(1)` to a point B in a medium where the speed of light is `v_(2)` as shown in figure is

Options

A. `t=(a sec i)/(v_(1))+(b sec r)/(v_(2))`
B. `t=(a sec i)/(v_(2))+(bsec r)/(v_(1))`
C. `t=(a sec i)/(v_(1))-(bsec r)/(v_(2))`
D. `t=(a sec i)/(v_(2))-(b sec r)/(v_(1))`

Answer

A