Question

All formulas from the 'Light' chapter.

Answer 1

All important formulas from the light chapter are given below :

1 . Mirror formula, $\frac{1}{v}+\frac{1}{u}=\frac{1}{f}$ (f is focal length, u is image distance and u is object distance)

2. Magnification (mirror) = $\frac{hightofimage}{hightofobject}=\frac{h_i}{h_o}=\frac{-v}{u}$ (hᵢ is image height and hₒ is object height)

3. Lens formula, $\frac{1}{v}-\frac{1}{u}=\frac{1}{f}$

5. Power of a lens, $P=\frac{1}{fcallength\left(f\right)}$

6. Absolute refractive index = $n=\frac{speedoflightinvacuum}{speedoflightinmedium}$

7. Relative refractive index = $n_{21}=\frac{speedoflightinmedium1}{speedoflightinmedium2}$

n21=speed of light in medium 1speed of light in medium 2n_{21}=\frac{\text{speed of light in medium 1}}{\text{speed of light in medium 2}}8. Snell's formula, $n=\frac{sini}{sinr}$ ('i' angle of incidence and 'r' angle of refraction)

9. Combine the power of two or more lenses, $P=P_1+P_2+P_3+..........$

10. Radius of curvature, =$2\times focallength=2f$​