15. Five marks exercise problem X

A hollow metallic cylinder whose external radius is \(4.3 \ cm\) and internal radius is \(1.1 \ cm\) and whole length is \(4 \ cm\) is melted and recast into a solid cylinder of \(12 \ cm\) long. Find the diameter of solid cylinder.

 

Answer:

 

The diameter of solid cylinder \(=\)  \(cm\)