Question

A. What type of pattern is produced by a double slit? single slit?

B. Why causes dark and bright fringes?

Answer 1

Answer A) In single slit diffration, light spreads out in a single line,producing no interesting phenomena.Here, the light spreads out in a line perpendicular to the slit.

But in double slit experiment, interference is seen where bright fringes and dark fringes are produced leading to constructive and destructive interference respectively. Here, a very bright spot at the center of the screen is formed called the central maxima.

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B) In double slit experiment, when two or more waves comes in phase with each other then a resultant wave of higher amplitude is foemed. It is called constructive interference and bright fringes are formed in it.

Now, when two or more waves are out of phase then the resultant wave of decreased amplitude is formed This is called destructive interference and dark fringes are forned in it.

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Good luck!:)