Moment of inertia

Question

A 0.225 m radius solid sphere has a

moment of inertia of 0.123 kg.m².

What is its mass?

[?] kg

can someone plz answer this thourghly ?

Answer 1

You must look up the moment of inertia for a sphere in a reference. If you do so, you'll find that, for a sphere, the moment of inertia (I) is 2/5mr²

So: 0.123 = (2/5)(m)(0.225)²

Solve for "m"