Advertisements
Advertisements
प्रश्न
Two cubes each of volume 27 cm3 are joined end to end to form a solid. Find the surface area of the resulting cuboid.
उत्तर
Let the edge of each cube be a cm.
Volume of each cube = a3 cm3
It is given that the volume of each cube is 27 cm3.
∴ a3 = 27= (3)3
⇒ a = 3
Thus, length of each edge of the cube = 3 cm
When two cubes are joined end-to-end, the solid obtained is a cuboid whose length, breadth and height are 6 cm, 3 cm and 3 cm respectively.
This can be diagrammatically shown as follows:
Surface area of the cuboid = 2 (lb + bh + hl)
= 2 (6 cm × 3 cm + 3 cm × 3 cm + 3 cm × 6 cm)
= 2 × 45 cm2
= 90 cm2
Thus, the surface area of the resulting cuboid is 90 cm2.
APPEARS IN
संबंधित प्रश्न
The internal and external diameters of a hollow hemisphere vessel are 21cm and 25.2 cm The cost of painting 1cm2 of the surface is 10paise. Find total cost to paint the vessel all
over______?
Prove that the surface area of a sphere is equal to the curved surface area of the circumference cylinder__?
A toy is in the shape of a right circular cylinder with a hemisphere on one end and a cone on the other. The radius and height of the cylindrical part are 5 cm and 13 cm respectively.The radii of the hemispherical and conical parts are the same as that of the cylindrical part.Find the surface area of the toy if the total height of the toy is 30 cm.
A metallic cylinder has radius 3 cm and height 5 cm. To reduce its weight, a conical hole is drilled in the cylinder. The conical hole has a radius of `3/2` cm and its depth is `8/9 `cm. Calculate the ratio of the volume of metal left in the cylinder to the volume of metal taken out in conical shape.
A solid metal sphere of 6 cm diameter is melted and a circular sheet of thickness 1 cm is prepared. Determine the diameter of the sheet.
Find the volume of a solid in the form of a right circular cylinder with hemi-spherical ends whose total length is 2.7 m and the diameter of each hemi-spherical end is 0.7 m.
From a cubical piece of wood of side 21 cm, a hemisphere is carved out in such a way that the diameter of the hemisphere is equal to the side of the cubical piece. Find the surface area and volume of the remaining piece.
The volume of a hemisphere is 19404 cm3. The total surface area of the hemisphere is
A solid cone of radius r and height h is placed over a solid cylinder having same base radius and height as that of a cone. The total surface area of the combined solid is `pir [sqrt(r^2 + h^2) + 3r + 2h]`.
The total surface area of a solid hemisphere of radius 7 cm is ______.
