A cylindrical brass bar of radius 2 cm and length 45 cm is melted and recast into…
MATHEMATICS · Multi-part · CBSE · Mathematics · Surface Areas and Volumes · Surface Areas and Volumes
Problem
A cylindrical brass bar of radius 2 cm and length 45 cm is melted and recast into identical hollow cylindrical pipes whose external radius is 1.5 cm, internal radius is 1 cm and length is 21 cm.
(i) Calculate the volume of the original brass bar.
(ii) Find the volume of one hollow pipe.
(iii) Determine the maximum number of complete pipes that can be produced.
(iv) If the outer curved surface area of one pipe is 198 cm2, find the percentage change in total curved surface area after recasting.