A circular disc of radius b has a hole of radius a at its center. if the mass per unit area of the disc varies as
Step 1: Given data:
The radius of gyration:
A diagram to represent the radius of gyration:
The formula of the radius of gyration:
Step 2: To find the radius of gyration:
We have,
Now,
So,
Now,
The radius of gyration:
Hence, then the radius of gyration of the disc about its axis passing through the centre is .