Question

A solid sphere, solid cylinder, and a hollow pipe all have equal masses and radii. If the three of them are released simultaneously at the top of an inclined plane and do not slip, which one will reach the bottom first?

Answer 1

Solid Sphere

Explanation:

According to the question, the three shapes have equal masses (m), radii (R) (and diameter).

The shape with the least mass moment of inertia will have the highest acceleration

Let IC represents Inertia

According to calculations, the inertia of

Solid Sphere: IC=(2/5)mR²

Solid Cylinder: IC=½mR²

Hollow Pipe: IC=⅔mR²

Where m = mass of the shape

And R is the Radius of the shape

By comparison, the solid sphere has the least mass of inertia and hollow Pipe has the most mass of inertia.

So, solid sphere will get to the bottom first.