1: Identify the two media and their refractive indices ($n_1$ and $n_2$). 2: Determine the angle of incidence ($\theta_1$). 3: Use Snell's Law ($n_1\sin(\theta_1) = n_2\sin(\theta_2)$) to solve for the angle of refraction ($\theta_2$).

1: Identify the object distance ($d_o$), image distance ($d_i$), and focal length ($f$). 2: Plug the known values into the thin lens equation: $\frac{1}{f} = \frac{1}{d_o} + \frac{1}{d_i}$. 3: Solve for the unknown variable.

Convex: Thicker in the middle, converges light. | Concave: Thinner in the middle, diverges light.

Concave: Reflecting surface curves inward, can form real or virtual images. | Convex: Reflecting surface curves outward, always forms virtual images.

Real: Formed by actual intersection of light rays, can be projected on a screen, $d_i$ is positive. | Virtual: Formed by apparent intersection of light rays, cannot be projected, $d_i$ is negative.

Interference: Superposition of two or more waves. | Diffraction: Bending of waves around obstacles or through apertures.

The light bends (refracts) towards the normal if the angle of incidence is not zero.

Constructive interference, resulting in a larger amplitude.

Destructive interference, resulting in cancellation or a smaller amplitude.

Diffraction, causing the light to spread out.