Question

9.15) What is the value of angle subtended at centre of sphere?​

Answer 1

Answer:

sr is the unit, steradian. Because the surface area A of a sphere is 4πr2, the definition implies that a sphere subtends 4π steradians (≈ 12.56637 sr) at itscenter. By the same argument, the maximum solid angle that can besubtended at any point is 4π sr.

Explanation:

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