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Karnataka Board PUCPUC Science 2nd PUC Class 12

A 100 m long antenna is mounted on a 500 m tall building. The complex can become a transmission tower for waves with λ.

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Question

A 100 m long antenna is mounted on a 500 m tall building. The complex can become a transmission tower for waves with λ.

Options

  • ~ 400 m

  • ~ 25 m

  • ~ 150 m

  • ~ 2400 m

MCQ
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Solution

~ 400 m

Explanation:

The length of the building is (l).

l = 500 m

and length of antenna = 100 m

and we know, the wavelength of the wave which can be transmitted by

L = `λ/4`

So, λ ~ 4l = 4 × 100 = 400 m

Wavelength (λ) is nearly equal to 400 m.

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Chapter 15: Communication Systems - Exercise [Page 98]

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NCERT Exemplar Physics Exemplar [English] Class 12
Chapter 15 Communication Systems
Exercise | Q 15.02 | Page 98

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