Question

A source emits electromagnetic waves of wavelength 3 m. One beam reaches the observer directly and other after reflection from a water surface, travelling 1.5 m extra distance and with intensity reduced to $\frac 14$ as compared to intensity due to the direct beam alone. The resultant intensity will be

• A. $(\frac 14)$ fold
• B. $(\frac 34)$ fold
• C. $(\frac 54)$ fold
• D. $(\frac 94)$ fold

Answer 1

Answer: (D)

$(\frac 94)$ fold

Answer 2

The correct option is (D): $(\frac 94)$ fold.