OP Malhotra Surface Area and Volume of 3D Solids Class-9 S.Chand ICSE Maths Ch-18

OP Malhotra Surface Area and Volume of 3D Solids (Cuboid and Cube) Class-9 S.Chand ICSE Maths Ch-18. We Provide Step by Step Answer of Exe-18(a), Exe-18(b), with Chapter Test of S Chand OP Malhotra Maths . Visit official Website CISCE  for detail information about ICSE Board Class-9.

OP Malhotra Surface Area and Volume of 3D Solids Class-9 S.Chand ICSE Maths Ch-18

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-: Select Topics :-

Exercise-18(a)

Exercise-18(b)

Chapter Test

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Exercise-18

OP Malhotra Surface Area and Volume of 3D Solids Class-9 S.Chand ICSE Maths Ch-18

Cuboid :

A cuboid is a three dimensional Shape. The cuboid is made from six rectangular faces, which are placed at right angles. The total surface area of a cuboid is equal to the sum of the areas of its six rectangular faces.

Lateral Surface Area of a Cuboid :

Lateral surface area (LSA) is the area of all the sides apart from the top and bottom faces.
The lateral surface area of the cuboid
= Area of face AEHD + Area of face BFGC + Area of face ABFE + Area of face DHGC
$=2(b\times h)+2(l\times h)$
LSA (cuboid) = 2h(l + b)

Cube :

A cuboid whose length, breadth and height are all equal, is called a cube. It is a three-dimensional shape bounded by six equal squares. It has 12 edges and 8 vertices.

Lateral Surface area of a cube :

Lateral surface area (LSA) is the area of all the sides apart from the top and bottom faces.
Lateral surface area of cube = $2(a\times a+a\times a)=4{\mathrm{a²}}^{}$

Right Circular Cylinder :

A right circular cylinder is a closed solid that has two parallel circular bases connected by a curved surface in which the two bases are exactly over each other and the axis is at right angles to the base.

The curved Surface area of a right circular cylinder :

Take a cylinder of base radius r and height h units. The curved surface of this cylinder, if opened along the diameter (d = 2r) of the circular base will be transformed into a rectangle of length $2\pi r$ and height h units.

Sphere :

A sphere is a closed three-dimensional solid figure, where all the points on the surface of the sphere are equidistant from the common fixed point called “centre”. The equidistant is called the “radius”.

Surface area of a Sphere :

The surface area of a sphere of radius r = 4 times the area of a circle of radius r $=4\times \left(\pi r^2\right)$
For a sphere Curved surface area (CSA) = Total Surface area(TSA) = $4\pi r^2$

Volume of a Cuboid :

The volume of a cuboid is the product of its dimensions.
Volume of a cuboid = $length\times breadth\times height=$ $lbh$
Where l is the length of the cuboid, b is the breadth, and h is the height of the cuboid.

Volume of a Cube :

The volume of a cube = $basearea\times height$.
Since all dimensions are identical, the volume of the cube $={\mathrm{a³}}^{}$
Where a is the length of the edge of the cube.

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Exercise-18 (a)

OP Malhotra Surface Area and Volume of 3D Solids Class-9 S.Chand ICSE Maths Ch-18

Question 1-

Find the surface area of the cuboids whose dimensions are  :

Question 28-

Two cubes each other of volume 343 cm³ are joined end to end. Find the surface area of the resulting cuboid.

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Exercise-18 (b)

OP Malhotra Surface Area and Volume of 3D Solids Class-9 S.Chand ICSE Maths Ch-18

Question 1-

Find the volume of the rail ……… 1.26 cm

Question 12-

In the …….. 20 m long

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Chapter Test

OP Malhotra Surface Area and Volume of 3D Solids Class-9 S.Chand ICSE Maths Ch-18

— : End of Surface Area and Volume of 3D Solids OP Malhotra S Chand Solutions :–

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Return to :–   OP Malhotra S Chand Solutions for ICSE Class-9 Maths

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