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A Navy captain going away a lighthouse a...

A Navy captain going away a lighthouse at the speed of `4[(sqrt3) - 1]` m/s. He observes that it takes him 1 minute to change the angle of elevation of the top of the lighthouse from `60^@` to `45^@`. What is the height (in metres) of the lighthouse?
एक नौसेना कप्तान `4[(sqrt3) - 1]` मी./से. की गति से लाइट हाऊस से दूर जा रहा है। वह निरीक्षण -करता है कि लाइट हाऊस की चोटी का उन्नयन कोण `60^@`से `45^@` बदलने के लिए उसे एक मिनट लगता है। लाइट हाऊस की ऊँचाई (मीटर में) क्या है?

A

`240sqrt(3)`

B

`480[(sqrt(3))-1]`

C

`360sqrt(3)`

D

`280sqrt(2)`

Text Solution

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The correct Answer is:
A
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