The radius of a hemisphere is the distance from the center of the circular base to any point on the curved surface. A hemisphere is half of a sphere, so if you know the radius of the sphere, it is the same as the radius of the hemisphere. This radius is crucial because it helps in calculating various properties of the hemisphere, such as its volume and surface area.
For example, if a sphere has a radius ‘r’, the radius of the corresponding hemisphere will also be ‘r’. Therefore, understanding the radius is fundamental to solving problems related to hemispheres in geometry.