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A solid metallic cube of side 6 cm is melted and recast into smaller cubes of side 2 cm. How many such smaller cubes can be made?
9
18
27
36
27
When a solid object is melted and recast into smaller objects of the same material, the total volume remains conserved. The number of smaller cubes is obtained by dividing the volume of the larger cube by the volume of one smaller cube.
When a solid object is melted and recast into smaller objects of the same material, the total volume remains conserved. The number of smaller cubes is obtained by dividing the volume of the larger cube by the volume of one smaller cube.
Imagine melting a large block of ice of volume 216 cubic centimeters and pouring the water into smaller ice cube trays each holding 8 cubic centimeters; you will be able to fill exactly 27 small trays.
Large Volume divided by Small Volume gives the count!
V=a3 тАФ Volume of a cube with side length a
n=VsmallтАЛVlargeтАЛтАЛ тАФ Number of smaller cubes formed
According to the principle of conservation of mass and volume in melting and casting processes, the volume of the original metal equals the sum of the volumes of all the recast items. The volume of a cube is given by V=a3, where a is the side length. Thus, the ratio of volumes gives n=VsmallтАЛVlargeтАЛтАЛ=2363тАЛ=8216тАЛ=27.
Volume remains constant during melting and recasting (neglecting negligible losses).
The side length of the large cube is 6 cm, making its volume 216extcm3.
The side length of each small cube is 2 cm, making its volume 8extcm3.
Quick computation using volume ratios rather than direct drawing or complex modeling.
Assumes 100% material efficiency without any melting waste or dross formation.
Foundry work and metal casting industries
Manufacturing identical components from bulk stock material
Density of the metallic material remains unchanged during the phase change and recasting.
Option A (9), Option B (18), and Option D (36) arise from incorrect exponent calculations or improper surface-to-volume ratio misunderstandings.
C is correct тАФ 27 smaller cubes of side 2 cm can be made from a solid metallic cube of side 6 cm due to the conservation of volume.
Always verify whether the problem asks for linear dimensions, surface areas, or volumes, as scaling factors differ (a for linear, a2 for area, and a3 for volume).