# Study Notes: SAT Physics Subject Test

## Optics

Speed of light: $\small c=3.00 \times 10^{8} m/s$

Young’s Double-slit interference experiment: $\small y_{m}=\frac{m \lambda L}{d}$ (d is the distance between two incidents)

Law of reflection: $\small \theta_{1}=\theta'_{1}$

Index of reflection: $\small n=\frac{c}{v}$ (v is the speed of light in specific materials)

Snell’s Law: $\small n_{1}sin\theta_{1}=n_{2}sin \theta_{2}$

Total internal reflection occurs when $\small n_{1} > n_{2}$ and $\small \theta_{1}>\theta_{c},\,\text{where}\,\theta_{c}=sin^{-1}(n_{2}/n_{1})$.

#### Mirrors

Mirror equation: $\small \frac{1}{s_{0}}+\frac{1}{s_{i}}=\frac{1}{f}$

Magnification equation: $\small m=-\frac{s_{i}}{s_{0}}$