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) + (b sec r)/(v_1)`
C. `t = (a sec i)/(v_1)- (b sec r)/(v_2)`
D. `t = (a sec i)/(v_2) - (b sec r)/(v_1)`

Answer

A