Superposition Principle

Two periodic waves of intensities I₁ and I₂ pass through a region at the same time in the same direction. The sum of the maximum and minimum intensities is:

1. $2\left({\mathrm{l}}_1+{\mathrm{l}}_2\right)$

2. ${\left({\sqrt{\mathrm{I}}}_1+{\sqrt{\mathrm{l}}}_2\right)}^2$

3. ${\left({\sqrt{\mathrm{I}}}_1-{\sqrt{\mathrm{l}}}_2\right)}^2$

4. $2\left({\sqrt{\mathrm{I}}}_1-{\sqrt{\mathrm{l}}}_2\right)$

An interference pattern is obtained with two coherent light sources of intensity ratio In the interference pattern, the ratio of their intensities will be:

1.		2.
3.		4.

Two coherent sources of light interfere and produce fringe patterns on a screen. For the central maximum, the phase difference between the two waves will be:
1. zero
2.
3.
4.