Question

The solid angle subtended at the center of sphere by an area of it's surface equal to the square of radius of the sphere is called ....?​

Answer 1

Answer:

steradian

Explanation:

• The International System of Units (SI) defines a steradian as the solid angle of a sphere subtended by a part of the surface whose area is equal to the square of the sphere's radius.
• A steradian is the solid angle subtended at the centre of a sphere of radius r by a surface area section of magnitude r 2.
• Because the surface area is 4r, a point in space is surrounded by 4 steradians.