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Question:

A ray of light travelling in water is incident on its surface open to air. The angle of incidence is θ, which is less than the critical angle. Then there will be,

Only a refracted ray and no reflected ray

A reflected ray and a refracted ray and, the angle between them would be less than 180°

Only a reflected ray and no refracted ray

A reflected ray and a refracted ray and the angle between them would be greater than 180°

Solution:

As long as the angle of incidence is less than the critical angle, fractions of light' intensity refracts out of the other side, and also a fraction of its intensity reflects back into the water. Clearly as shown in the figure, the angle between them is less than 180°.