A point p is situated `90.50cm and 90.58` cm away from two coherent sources. The nature of illumination of the point p of the wavelength of light is 400Å is,

Options

A. bright
B. dark
C. neither bright nor bark
D. noen of these

Answer

A

Explanation

Path diff. `=9.58-90.50= 0.08 cm `
Now, `n=("Path diff")/("Wavelength")=(0.08xx10^(-2))/(4xx10^(-7))=2000`
The pathh diff. `= 2000 lambda`= inegral multiple of wavelenght, point up appears as bright.