Advertisements
Advertisements
प्रश्न
If the length of a diagonal of a cube is `8 sqrt(3)` cm, then its surface area is
विकल्प
512 cm2
384 cm2
192 cm2
768 cm2
Advertisements
उत्तर
Let,
a→ Side of the cube
Length of the diagonal = 8`sqrt(3) ` cm
`sqrt(3a) = 8 sqrt(3)`
a = 8 cm
We have to find the surface area of the cube
Surface area of the cube,
`=6a^2`
`=6xx8^2`
`=384 cm^2`
Thus, surface area of the cube is 384 cm2 .
APPEARS IN
संबंधित प्रश्न
A cuboidal block of silver is 9 cm long, 4 cm broad and 3.5 cm in height. From it, beads of volume 1.5 cm3 each are to be made. Find the number of beads that can be made from the block.
A tank is 8 m long, 6 m broad and 2 m high. How much water can it contain?
An 8 m long cuboidal beam of wood when sliced produces four thousand 1 cm cubes and there is no wastage of wood in this process. If one edge of the beam is 0.5 m, find the third edge.
A classroom is 7 m long, 6 m broad and 3.5 m high. Doors and windows occupy an area of 17 m2. What is the cost of white-washing the walls at the rate of Rs 1.50 per m2.
The areas of three adjacent faces of a cuboid are x, y and z. If the volume is V, prove that V2 = xyz.
A closed iron tank 12 m long, 9 m wide and 4 m deep is to be made. Determine the cost of iron sheet used at the rate of Rs 5 per metre sheet, sheet being 2 m wide.
Four cubes, each of edge 9 cm, are joined as shown below :
Write the dimensions of the resulting cuboid obtained. Also, find the total surface area and the volume
A room is 22m long, 15m broad and 6m high. Find the area of its four walls and the cost of painting including doors and windows at the rate of Rs.12per m2.
The dimensions of a hall is 10 m × 9 m × 8 m. Find the cost of white washing the walls and ceiling at the rate of ₹ 8.50 per m2
