Which is false in case of a hollow cylinder?

A hollow cylinder is a 3D object with two circular surfaces—an inner and an outer. It is commonly shaped like a pipe or a tube.

Defined by:

• Outer radius: R
• Inner radius: r
• Height: h

True Properties of a Hollow Cylinder

• Volume: πh(R² - r²)
• Curved Surface Area (CSA): 2πh(R + r)
• Total Surface Area (TSA): 2πh(R + r) + 2π(R² - r²)
• If R = r, it becomes a solid cylinder.

Why This Statement Is False:

A hollow cylinder actually has two curved surfaces:

• An outer curved surface (with radius R)
• An inner curved surface (with radius r)

Therefore, saying it has only one curved surface is incorrect.

Final Answer:

The false statement is: “A hollow cylinder has only one curved surface.”