Introduction:
When a light ray travels from one medium to another, it undergoes refraction and reflection. The angles of incidence and reflection are related to each other by the laws of reflection. In this case, we are given the angle of incidence for reflection when a light ray travels from air to glass. We need to find the incident angle for reflection when the light ray travels from water to glass.

Understanding the Situation:
1. Angle of incidence for reflection from air to glass = 57 degrees.
2. We need to find the incident angle for reflection from water to glass.

Applying the Laws of Reflection:
1. The angle of incidence is equal to the angle of reflection.
2. The incident ray, reflected ray, and the normal to the surface at the point of incidence all lie in the same plane.

Solution:
1. Let's assume the angle of incidence for reflection when the light ray travels from water to glass is θ.
2. Using the laws of reflection, we know that the angle of incidence is equal to the angle of reflection. Therefore, the angle of reflection would also be θ.
3. The incident ray, reflected ray, and the normal to the surface at the point of incidence all lie in the same plane. Hence, the normal to the surface will be the same for both cases (air to glass and water to glass).
4. Since the normal remains the same, the angle between the incident ray and the normal will also remain the same. Therefore, the angle of incidence from water to glass will also be 57 degrees.

Conclusion:
When a light ray incident from air to glass has a reflected angle of incidence of 57 degrees, the incident angle for reflection again when the light ray is incident from water to glass will also be 57 degrees. This is because the angle of incidence is equal to the angle of reflection, and the normal to the surface remains the same in both cases.

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