A cone, a hemisphere and a cylinder -Maths 9th

A cone, a hemisphere and a cylinder -Maths 9th
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Answer :

V1 (volume of cone) = 1/3 πr2r V2 (volume of hemisphere) = 2/3 πr3 V3 (volume of cylinder) =  πr2 .r V1: V2: V3 = 1/3 πr3 : 2/3πr3 : πr3  =  1/3 : 2/3 : 1 V 1: V 2: V 3 = 1 : 2 : 3
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Related questions

A storage tank consists of a circular cylinder with a hemisphere adjoined on either end. If the external diameter of the cylinder be 1.4 m and its length be 8 m, find the cost of painting it on the outside at the rate of Rs. 10 per m -Maths 9th

Description : A storage tank consists of a circular cylinder with a hemisphere adjoined on either end. If the external diameter of the cylinder be 1.4 m and its length be 8 m, find the cost of painting it on the outside at the rate of Rs. 10 per m -Maths 9th

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Description : Find the total surface area of a hemisphere of radius 10 cm -Maths 9th

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Description : The outer curved surface areas of the hemisphere and sphere are in ratio 2:9. find their ratio of their raddii -Maths 9th

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Description : The outer curved surface areas of the hemisphere and sphere are in ratio 2:9. find their ratio of their raddii -Maths 9th

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Description : Define : Hemisphere. -Maths 9th

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Last Answer : Given: Radius of cone, r = diameter/2 = 40/2 cm = 20cm = 0.2 m Height of cone, h = 1m Slant height of cone is l, and l2 = (r2+h2) Using given values, l2 = (0.22+12) = (1.04) Or l ... (32.028 12) = Rs.384.336 = Rs.384.34 (approximately) Therefore, the cost of painting all these cones is Rs. 384.34.

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Description : Curved surface area of a cone is 308 cm2 and its slant height is 14 cm. Find (i) radius of the base -Maths 9th

Last Answer : Slant height of cone, l = 14 cm Let the radius of the cone be r. (i) We know, CSA of cone = πrl Given: Curved surface area of a cone is 308 cm2 (308 ) = (22/7) r 14 308 = 44 r r = 308 ... Total surface area of cone = 308+(22/7) 72 = 308+154 Therefore, the total surface area of the cone is 462 cm2.

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Last Answer : Circumference of the base of a cone = 2πr

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Last Answer : Here, radius (r) = 3.5 cm and height (h) = 12 cm ∴ Amount of ice cream = 1 / 3 πr2h = 1 / 3 × 22 / 7 × 3.5 × 3.5 × 12 = 154 cm3

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Description : A cone is 8.4 cm high and the radius of its base is 2.1 cm. -Maths 9th

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A heap of wheat is in the form of a cone whose diameter is 10.5 m and height is 3 m. -Maths 9th

Description : A heap of wheat is in the form of a cone whose diameter is 10.5 m and height is 3 m. -Maths 9th

Last Answer : Diameter of cone = 10.5 m Radius of cone (r) = 5.25 m Height of cone (h) = 3 m Volume of cone = 1 / 3 πr2h = 1 / 3 × 22 / 7 × 5.25 × 5.25 × 3 = 86.625m3 Cost of 1m3 of wheat = 10 ∴ Cost of 86.625 m3 of wheat = 10 × 86.625 = 86.625

A cone is 8.4 cm high and the radius of its base is 2.1 cm. It is melted and recast into a sphere. -Maths 9th

Description : A cone is 8.4 cm high and the radius of its base is 2.1 cm. It is melted and recast into a sphere. -Maths 9th

Last Answer : NEED ANSWER

The total surface area of a cone whose radius is r/2 and slant height 2l is -Maths 9th

Description : The total surface area of a cone whose radius is r/2 and slant height 2l is -Maths 9th

Last Answer : Total surface area of cone = πr(r+l) Given, radius = r/2​ and slant height = 2l Therefore, new total surface area of cone = πr/2​(r​/2+2l) = π(r/4^2​+rl) = πr(l+r/4​)

A cone is 8.4 cm high and the radius of its base is 2.1 cm. It is melted and recast into a sphere. -Maths 9th

Description : A cone is 8.4 cm high and the radius of its base is 2.1 cm. It is melted and recast into a sphere. -Maths 9th

Last Answer : According to question find the radius of the sphere

The total surface area of a cone whose radius is r/2 and slant height 2l is -Maths 9th

Description : The total surface area of a cone whose radius is r/2 and slant height 2l is -Maths 9th

Last Answer : Radius (r)=r/2 & slant height=2l TSA (S)=PIE R (l+r) =22/7×r/2(2l+r/2) =11/7×r(2l+r/2)

Diameter of the base of a cone is 10.5 cm -Maths 9th

Description : Diameter of the base of a cone is 10.5 cm -Maths 9th

Last Answer : Radius of cone (r) = 10.5/2 cm Slant height of cone (l) = 10 cm Curved surface area of cone = πrl = 22/7 x 10.5/2 x 10 = 165 cm2

Curved surface area of a cone is -Maths 9th

Description : Curved surface area of a cone is -Maths 9th

Last Answer : Slant height of the cone (l) = 14 cm Curved surface area of the cone = 308 cm2 Let 'r' be the radius of the base of cone (i) Curved surface area of cone = πrl ∴ 22/7 x r x 14 = 308 ⇒ r = 308 x 7/22 x 14 ... ii) Total surface area of cone = πr(r + l) = 22/7 x 7(7 + 14) = 22/7 x 7 x 21 = 462 cm2

The radius and slant height of a cone... -Maths 9th

Description : The radius and slant height of a cone... -Maths 9th

Last Answer : Let the radius of cone (r) = 4x cm and the slant height of the cone (l) = 7x cm Curved surface area of cone = πrl ∴ πrl = 792 cm2 ⇒ 22/7 x 4x x 7x = 792 ⇒ x2 = 792/22 x 4 = 9 ⇒ x = 3 cm ∴ Radius of the cone = 4 x 3 = 12 cm

The radius and height of a cone are in the ratio 3 : 4 -Maths 9th

Description : The radius and height of a cone are in the ratio 3 : 4 -Maths 9th

Last Answer : Let the radius ofthe cone (r) = 3x cm Height of the cone (h) = 4x cm Volume of the cone = 1/3 πr2h ⇒ 301.44 = 1/3 x 3.14 x (3x)2 .4x ⇒ x3 = 301.44/3.14 x 12 = 8 ⇒ x3 = 23 ⇒ x = 2 ... 4 x 2 = 8 cm Slant height of the cone (l) = root under (√r2 + h2 ) = root under (√62 + 82)= √100 = 10 cm

The height of a cone is 15 cm. -Maths 9th

Description : The height of a cone is 15 cm. -Maths 9th

Last Answer : Let, the radius of the base of cone be r cm Height of the cone = 15 cm Volume of the cone = 1570 cm3 ⇒ 1/3πr2h = 1570 ⇒ 1/3 x 3.14 x r2 x 15 = 1570 ⇒ r2 = 1570 x 3/3.14 x 15 = 100 ⇒ r = √100 = 10 cm Thus, the diameter of the base of the cone = 2r = 2 x 10 cm = 20 cm

The volume of a right circular cone is 9856 cmcube. -Maths 9th

Description : The volume of a right circular cone is 9856 cmcube. -Maths 9th

Last Answer : Let the height of the cone be h cm. Radius of the base of the cone (r) = 28/2 cm = 14 cm Volume of the cone = 9856 cm3 ⇒ 1/3πr2h = 9856 ⇒ 1/3 x 22/7 x 14 x 14 x h = 9856 ⇒ h = 9856 x 7 x 3/ ... √196 + 2304) = √2500 ∴ l = 50 cm (iii) Curved surface area of cone = πrl = 22/7 x 14 x 50 = 2200 cm2

A heap of wheat is in the form of a cone whose diameter is 10.5 m -Maths 9th

Description : A heap of wheat is in the form of a cone whose diameter is 10.5 m -Maths 9th

Last Answer : Radius of the conical heap of wheat (r) = 10.5/2 m Height of the conical heap of wheat (h) = 3 m Volume of the conical heap of wheat = 1/3 πr2h = 1/3 x 22/7 x (10.5/2)2 x 3 = 173.25/2 = 86.625 ... = 6.05 m Area of canvas required = curved surface area of cone πrl = 22/7 x 10.5/2 x 6.05 = 99.825 m2

A cone of height 24 cm has a curved surface -Maths 9th

Description : A cone of height 24 cm has a curved surface -Maths 9th

Last Answer : Height of the cone (h) = 24 cm Let r сm be the radius of the base and l cm be the slant height of the cone. Then, l = root under (√r2+ h2 ) = root under (√r2 + 242) = root under (√r2 + 576) Now, Curved surface ... ⇒ r = 7 cm ∴ Volume of the cone = 1/3πr2h = 1/3 x 22/7 x 72 x 24 = 1232 cm3

Define : Right circular cone. -Maths 9th

Description : Define : Right circular cone. -Maths 9th

Last Answer : A right circular cone is a cone where the axis of the cone is the line meeting the vertex to the midpoint of the circular base. That is, the centre point of the circular base is joined with ... cone is a three-dimensional shape having a circular base and narrowing smoothly to a point above the base.

There are two identical cubes. Out of one cube, a sphere of maximum volume (VS) is cut off. Out of the second cube, a cone of maximum volume -Maths 9th

Description : There are two identical cubes. Out of one cube, a sphere of maximum volume (VS) is cut off. Out of the second cube, a cone of maximum volume -Maths 9th

Last Answer : answer:

In a sphere of radius 2 cm a cone of height 3 cm is inscribed. What is the ratio of volumes of the cone and sphere ? -Maths 9th

Description : In a sphere of radius 2 cm a cone of height 3 cm is inscribed. What is the ratio of volumes of the cone and sphere ? -Maths 9th

Last Answer : answer:

A cone of height 7 cm and base radius 1 cm is carved from a cuboidal block of wood 10 cm × 5 cm × 2 cm -Maths 9th

Description : A cone of height 7 cm and base radius 1 cm is carved from a cuboidal block of wood 10 cm × 5 cm × 2 cm -Maths 9th

Last Answer : 92239223% Volume of cone = 1313πr2h = 13×227×1×7=22313×227×1×7=223 cu. cm Volume of cubical block = (10 × 5 × 2) cm3 = 100 cm3 ∴ Wastage of wood = (100−227)100×100(100−227)100×100 = 27832783% = 92239223%

If S denotes the area of the curved surface of a right circular cone of height h end semi-vertical angle a, then S equals -Maths 9th

Description : If S denotes the area of the curved surface of a right circular cone of height h end semi-vertical angle a, then S equals -Maths 9th

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Description : A sphere and a right circular cone of same radius have equal volumes. By what percentage does the height of the cone exceed its diameter ? -Maths 9th

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A child consumed an ice-cream of inverted right-circular conical shape from the top and left only 12.5% of the cone for her mother. -Maths 9th

Description : A child consumed an ice-cream of inverted right-circular conical shape from the top and left only 12.5% of the cone for her mother. -Maths 9th

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A sphere and a cone have equal bases. If their heights are also equal, the ratio of their curved surface will be : -Maths 9th

Description : A sphere and a cone have equal bases. If their heights are also equal, the ratio of their curved surface will be : -Maths 9th

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What is the volume of cone ? -Maths 9th

Description : What is the volume of cone ? -Maths 9th

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the curved surface area of a cylinder is 154 cm. the total surface area of the cylinder is three times its curved surface area. find the volume of the cylinder. -Maths 9th

Description : the curved surface area of a cylinder is 154 cm. the total surface area of the cylinder is three times its curved surface area. find the volume of the cylinder. -Maths 9th

Last Answer : T.S.A = 3*154 = 462 cm² C.S.A = 154 cm² C.S.A = 2πrh T.S.A = 2πr(r+h) Now, In T.S.A = 2πrr + 2πrh 462 = 2πrr + 2πrh 462 = 2*22/7*r*r + 154 462 - 154 = 2*22/7*r*r 308*7/2*22 = r*r 49 = r*r R = 7 cm ... 7*h 154/44 = h 7/2 =h H = 3.5 cm or 7/2 cm Now volume = πrrh = 22/7 * 7* 7 *7/2 = 11*49 = 539 cm³