Question

When two coherent sources each of individual intensity \( I_0 \) interfere, the resultant intensity due to constructive and destructive interference are respectively

• A. \( 4I_0 { and } 0 \)
• B. \( I_0 { and } 2I_0 \)
• C. \( 0 { and } 2I_0 \)
• D. \( 2I_0 { and } I_0 \)
• E. \( 2I_0 { and } 0 \)

Hint:

Remember, for constructive interference, the intensities add up, and for destructive interference, the intensities subtract, possibly resulting in complete cancellation.

Answer 1

The Correct Option is A

Step 1: For two coherent sources, the resultant intensity due to constructive interference is given by: \[ I_{{constructive}} = (I_0 + I_0)^2 = 4I_0. \] Step 2: For destructive interference, the intensity becomes: \[ I_{{destructive}} = (I_0 - I_0)^2 = 0. \] Thus, the resultant intensities are \( 4I_0 \) due to constructive interference and 0 due to destructive interference.