Angle of incidence/° Angle of refraction/°

Question

30° 22°
50° 15°
20° 11°

In the refraction experiment, analyze how the angles of incidence and refraction relate to each other and to the material. The materials were glass block, pin and white sheet of paper.

Answer 1

In the refraction experiment you provided, we can analyze the relationship between the angles of incidence and refraction, as well as the properties of the materials involved in the experiment.

Relationship Between Angle of Incidence and Angle of Refraction

1. Snell's Law: The relationship between the angle of incidence (i) and the angle of refraction (r) is described by Snell's Law: \[ n_1 \sin(i) = n_2 \sin(r) \] Here, \( n_1 \) and \( n_2 \) are the refractive indices of the two media (when light travels from one medium to another).

2. Data Analysis:

   • For the data provided:

     • When \( i = 30^\circ \), \( r = 22^\circ \)
     • When \( i = 50^\circ \), \( r = 15^\circ \)
     • When \( i = 20^\circ \), \( r = 11^\circ \)

   • From the experiment, you can see that as the angle of incidence increases, the angle of refraction does not increase proportionally. For instance, when the angle of incidence was 30°, the angle of refraction was 22°, which implies some bending of light. However, at 50°, the angle of refraction dropped significantly to 15°. This represents a decrease in the angle of refraction despite an increase in incidence, which indicates that the light is entering a denser medium.

3. Interpretation:

   • The data suggests that the material has a specific refractive index that causes light to slow down as it enters the medium (glass), resulting in a smaller angle of refraction when the angle of incidence increases.
   • This also indicates that the material (glass) is denser compared to air, which is consistent with known optical properties: glass generally has a higher refractive index than air (approximately 1.5 for glass compared to 1.0 for air).

Materials Used

1. Glass Block: This is the medium that causes refraction. The refractive index of glass will determine how much the light bends as it passes through.

2. Pin: Used as a reference point to observe the path of light. It helps in marking the angles of incidence and refraction accurately.

3. White Sheet of Paper: Likely serves as the surface on which the light path was projected or helps to visualize the light pattern.

Conclusion

In summary, the experiment demonstrates that the angles of incidence and refraction are related through Snell's Law, emphasizing that different materials cause light to bend at different angles based on their respective refractive indices. The significant variation between the angles of incidence and refraction in the provided data indicates how light slows down and bends upon entering a denser medium like glass from air. Each angle recorded demonstrates the property of the material and supports the idea that the behavior of light is predictable based on established physical laws.