Plot a graph of y against sin i Find K = S' State two precautions taken to ensure accurate results. Distinguish between reflection and refraction of light. A ray of light is incident at an angle of 30° to the normal, is deviated through an angle of 53° in a rectangular prism.

Let $(\sin i_1, y_1) = (0.866, 0.60)$ and $(\sin i_2, y_2) = (0.766, 0.53)$.

The value of K (the slope) is $\boxed{\text{0.70}}$.

3. State two precautions taken to ensure accurate results
Two precautions to ensure accurate results in an optics experiment are:

• Ensure the optical components (e.g., prism, lens, pins) are clean and free from dust or smudges.
• Use a sharp pencil to mark points on the paper to minimize errors in measurement and avoid parallax error when reading scales or angles.

4. Distinguish between reflection and refraction of light

• Reflection is the phenomenon where light bounces off a surface and returns into the same medium. The angle of incidence equals the angle of reflection.
• Refraction is the phenomenon where light passes from one medium to another, causing it to change direction due to a change in speed. This bending of light is governed by Snell's Law.

5. A ray of light incident at an angle of 30° to the normal is deviated through an angle of 10.53° in a rectangular prism.
We will calculate the refractive index of the prism.

Angle of incidence, $i = 30^\circ$.
Angle of deviation, $D = 10.53^\circ$.

When light enters a denser medium (like a prism from air), it bends towards the normal. The deviation is given by the difference between the angle of incidence and the angle of refraction:

Snell's Law states $n_1 \sin i = n_2 \sin r$. Assuming light travels from air ($n_1 = 1$) into the prism ($n_2 = n$):

The refractive index of the prism is approximately $\boxed{\text{1.500}}$.