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Two towers on top of two hills are 40 km...

Two towers on top of two hills are 40 km apart. The line joining them passes 50 m above a hill halfway between the towers. What is the longest wavelength of radio waves, which can be sent between the towers without appreciable diffraction effects?

A

125 cm

B

`12.5 cm`

C

`1.25 cm`

D

`0.125 cm`

Text Solution

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The correct Answer is:
B
For answer see Physics Darpan, Part-2, Section-B, Exercises of Textbook example no. 10.18
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