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Syeda answered 1 year(s) , 10 month(s) ago

Find the length of the longest rod that can be placed in a room

Given length l = 12 m
breadth b = 9 m and height h = 8 m
Longest rod that can be placed in a room is nothing but its diagonal.
Length of diagonal of a cuboid = √...

Oct 11

• 1 Like
• 62422 Views

Oct 11

Syeda answered 1 year(s) , 10 month(s) ago

A cone ,hemisphere and a cylinder stand on equal base

Volume of cone = (1/3)πr 2h
Volume of hemisphere = (2/3)πr 3
Volume of cylinder = πr 2h
Given that cone, hemisphere and cylinde...

Jan 9

• 5 Likes
• 59812 Views

Jan 9

Syeda answered 1 year(s) , 10 month(s) ago

A semi circular sheet of metal of diameter 28 cm

Given diameter = 28 cm
Radius, r = 14 cm
Circumference of semi circle = πr
= (22/7) x 14 = 44 cm
This becomes circumference of base of cone
2 πR =...

Feb 27

• 5 Likes
• 51630 Views

Feb 27

Raghunath answered 4 year(s) , 1 month(s) ago

A sphere and a cube have the same surface area . show that the ratio of the volumes of the sphere to that of the cube is √6 : √π

Let r and a be the radius of the sphere and edge of the cube respectively.

Given, Surface area of sphere = Surface area of cube

4πr2 = 6a2

(r/a

...

Mar 9

• 4 Likes
• 48508 Views

Mar 9

Syeda answered 1 year(s) , 10 month(s) ago

The outer dimensions of a closed wooden box are 10 cm x 8 cm x 7 cm.

Given outer length = 10 cm
Outer breadth = 8 cm
Outer height = 7 cm
Outer volume = length × breadth × height
= 10 × 8 × 7 = 560 cm3
Thickness of wood

...

Oct 16

• 3 Likes
• 40556 Views

Oct 16

Raghunath answered 4 year(s) , 2 month(s) ago

Three cubes each of side 5 cm are joined to the end. find the surface area of the resultant cuboid.

Sol:

Given, each side of the cube is 5 cm.

When three cubes are joined end to end, then the resulting solid is a cuboid.

Length of the cuboid, l = 2 × each side of the cube = 2 × 5

...

Feb 4

• 2 Likes
• 36950 Views

Feb 4

Raghunath answered 4 year(s) , 11 month(s) ago

AB and CD are 2 parallel chords of a circle such that AB=10cm CD =24cm if 2 chords are on the opp side of the centre and the distance bw them is 17cm find the radius of

Sol :

Given AB and CD are two chords of a circles D and E are midpoints of AB ,CD respectively.
CD = DB = 12 cm and AE = EB = 5 cm
Distance between two chords = 17 cm
Di...

Mar 1

• 2 Likes
• 31599 Views

Mar 1

daniel answered 1 year(s) , 1 month(s) ago

Write all the formulas in Surface areas and volumes.

Sol:
If l, b and h are length, breadth and height of a cuboid, then
•  lateral surface area = 2h (l + b)
•  total surface area of the cuboid = 2(lb + bh + lh)
...

Nov 29

• 3 Likes
• 29809 Views

Nov 29

Ramesh answered 4 year(s) , 1 month(s) ago

The length of longest pole that can be put in a room of dimensions (10m x 10m x 5m) is _________.

Length of the longest pole that can be put in a room = Length of the diagonal inside the room

Length of the diagonal =  √( l 2   + b 2...

Mar 9

• 6 Likes
• 29534 Views

Mar 9

Raghunath answered 4 year(s) , 1 month(s) ago

A sphere ,cylinder and a cone of same radius and same height find the ratio of their CSA

Since, the height of a sphere is the diameter, the cone and cylinder have height 2r.

Then
Curved surface area of Sphere= 4πr²

Curved surface area of cylinder = 2πr(2r) = 4πr²

...

Feb 24

• 2 Likes
• 27924 Views

Feb 24

Agam answered 1 year(s) , 7 month(s) ago

A well with inside diameter of 10m is dug 14m deep

Given radius of the well = 5 m
Height of the well = 14 m
Width of the embankment = 5 m
Therefore radius of the embankment = 5 + 5 = 10 m
Let h be the height of the embankment...

Mar 13

• 1 Like
• 26591 Views

Mar 13

Aditya answered 4 year(s) , 1 month(s) ago

How many meters of cloth 5m wide will be required to make a conical tent,the radius of whose base is 7m and whose height is 24m?

Given, r = 7 m

h = 24 m

∴ slant height l = √(r2 + h2) = √(49 + 576) = √625 = 25 m

CSA of the cone = πrll = 22/7 x 7 x 25 = 550 m2

Area of the

...

Mar 3

• 2 Likes
• 23713 Views

Mar 3

Agam answered 1 year(s) , 5 month(s) ago

A solid iron rectangular block of dimensions 4.4 m, 2.6 m and 1 m

Internal radius, r = 30 cm
Thickness, w = 5 cm
External radius, R = 30 + 5 = 35 cm
Here volume of cuboid = volume of hollow cylinder
440 × 260 ×100 = π(R 2 – r 2) h
⇒...

Oct 19

• 0 Like
• 22812 Views

Oct 19

Raghunath answered 4 year(s) , 3 month(s) ago

The surface areas of two spheres are in the ratio 1:4.find the ratio of their volumes.

Sol:
Given that surface areas of two spheres are in the ratio 1:4.

4πr² : 4πR²  = 1 : 4

r : R = 1 : 2.

Now ratio of volumes of two spheres  =  (4/3)πr3 : (4/3)πR

...

Asked by L srinivasulu

Dec 21

• 1 Like
• 20806 Views

Asked by L srinivasulu

Dec 21

Kishore answered 5 year(s) , 5 month(s) ago

A cylinder of radius 12cm contains water to a depth of 20cm.

Given radius of the cylinder, r = 12 cm
It is also given that a spherical iron ball is dropped into the cylinder and the water level raised by 6.75 cm
Hence volume of water displaced = volume of...

Oct 16

• 3 Likes
• 19672 Views

Oct 16

Raghunath answered 4 year(s) , 4 month(s) ago

Find the outer and inner radii of the pipe.

Sol:

Let r and R be the inner and outer radius of the cylindrical metallic pipe respectively.

h be the height of the metallic pipe = 14 cm

Difference between the Curved surface a

...

Nov 22

• 1 Like
• 17285 Views

Nov 22

Kishore answered 5 year(s) , 4 month(s) ago

The diameter of a sphere is decreased by 25%

Curved surface area of the sphere = 4πr 2

Given diameter is decreased by 25%
Hence the new diameter=

Asked by Sunil dhikle

Nov 23

• 0 Like
• 16831 Views

Asked by Sunil dhikle

Nov 23

Kishore answered 5 year(s) , 3 month(s) ago

if v is volume of cubiod of dimensions a,b,c

Given dimensions of cuboid are a, b and c.
Therefore, volume of cuboid, V = abc  → (1)
Surface area of cuboid, S = 2(ab + bc + ca)   → (2)
Now divide (2) with (1), we get
...

Jan 4

• 5 Likes
• 16808 Views

Jan 4

Kishore answered 4 year(s) ago

A right angled triangle ABC with sides 5cm, 12cm, 13cm is revolved

Given a right angle triangle with sides 5cm, 12 cm and 13 cm
Hence hypotenuse is 13 cm
Given that the triangle is revolved about 12 cm side
Therefore, radius r = 5 cm and height  h = 12...

Mar 5

• 0 Like
• 16113 Views

Mar 5

Kishore answered 5 year(s) , 6 month(s) ago

The diagonal of cube is √12 cm . What is its edge?

Given length of diagonal of a cube = √12 cm
Recall that length of diagonal of a cube = √3 × Length of edge of the cube
⇒ √12 = √3 × Length of edge of the cube
∴  Length of edge of the cu...

Oct 11

• 3 Likes
• 15641 Views

Oct 11

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