Twenty-seven solid iron spheres, -Maths 9th

Twenty-seven solid iron spheres, -Maths 9th
by

1 Answer

Answer :

(i) Volume of 27 solid sphere, each of radius, r = 27 x 4/3 πr3 = 36 πr3 According to statement,  Volume of sphere of radius r' = Volume of 27 solid spheres ⇒  4/3 π(r'3 ) = 36 πr3 ⇒   (r')3  = 27r3 = (3r)3 ⇒  r' = 3r  (ii) We have, S' = 4 πr'2 = 4 π(3r)2 = 36 πr2  ∴    S/S' =  4 πr2 /36 πr2 = 1/9 ⇒ S : S' = 1 : 9
by

Related questions

Two solid spheres made of the same metal have weights 5920 g and 740 g, respectively. -Maths 9th

Description : Two solid spheres made of the same metal have weights 5920 g and 740 g, respectively. -Maths 9th

Last Answer : NEED ANSWER

Two solid spheres made of the same metal have weights 5920 g and 740 g, respectively. -Maths 9th

Description : Two solid spheres made of the same metal have weights 5920 g and 740 g, respectively. -Maths 9th

Last Answer : Solution of this question

Two solid spheres made of the same metal -Maths 9th

Description : Two solid spheres made of the same metal -Maths 9th

Last Answer : Let r and R be the radii of the smaller and larger spheres respectively. We have, r = 5/2 cm Volume of the smaller sphere = 4/3πr3 = 4/3π(5/2)3 cm3 = 4/3 x π x 125/8 cm3 Density of metal = Mass/Volume = 740/4/3 x 125/8π ... ⇒ R3 = 5920 x 125/740 x 8 = 125 ⇒ R3 = 53 ⇒ R = 5 cm

Metal spheres, each of radius 2 cm, are packed into a rectangular box of internal dimensions 16 cm x 8 cm x 8 cm. -Maths 9th

Description : Metal spheres, each of radius 2 cm, are packed into a rectangular box of internal dimensions 16 cm x 8 cm x 8 cm. -Maths 9th

Last Answer : Volume of rectangular box=lbh=16(64)=1024cm3 Volume of sphere=34​πr3=33.5238cm3 16 sphere=16(33.5238)=536.3808 Volume of liquid=1024−536.3808=488cm3

Metal spheres, each of radius 2 cm, are packed into a rectangular box of internal dimensions 16 cm x 8 cm x 8 cm. -Maths 9th

Description : Metal spheres, each of radius 2 cm, are packed into a rectangular box of internal dimensions 16 cm x 8 cm x 8 cm. -Maths 9th

Last Answer : According to question find the volume of this liquid.

The volume of two spheres are in the -Maths 9th

Description : The volume of two spheres are in the -Maths 9th

Last Answer : Let r1 and r2 be the radii of two spheres . Then, the ratio of their volumes is given by 4/3πr13/4/3πr23 = 64/27 (r1/r2)3 = (4/3)3 ⇒ r1/r2 = 4/3 Now, ratios of surface areas of two spheres = 4/3πr12/4/3πr22 = (r1/r2)2 = (4/3)2 = 16/9 ∴ Required ratio = 16 : 9

The volumes of two spheres are in the ratio 64 : 27. Find the difference of their surface areas, if the sum of their radii is 7 cm. -Maths 9th

Description : The volumes of two spheres are in the ratio 64 : 27. Find the difference of their surface areas, if the sum of their radii is 7 cm. -Maths 9th

Last Answer : answer:

The sum of the radii of two spheres is 10 cm and the sum of their volumes is 880 cm^3. What will be the product of their radii ? -Maths 9th

Description : The sum of the radii of two spheres is 10 cm and the sum of their volumes is 880 cm^3. What will be the product of their radii ? -Maths 9th

Last Answer : answer:

A spherical metal of radius 10 cm is melted and made into 1000 smaller spheres of equal sizes. In this process the surface area of the -Maths 9th

Description : A spherical metal of radius 10 cm is melted and made into 1000 smaller spheres of equal sizes. In this process the surface area of the -Maths 9th

Last Answer : Option (C) is correct. Solution: Let the radius of the small spheres be r' cm. Volume of metal remains the same in both cases. So, vol of the spherical metal of radius 10 cm = total ... Total Surface area of 1000 smaller spheres: 1000*4π12 = 4000π Hence, the surface area increased by 10 times.

Three identical balls fit snugly into a cylindrical can. The radius of the spheres is equal to the radius of the can and the balls just touch the -Maths 9th

Description : Three identical balls fit snugly into a cylindrical can. The radius of the spheres is equal to the radius of the can and the balls just touch the -Maths 9th

Last Answer : hope its clear

A fair dice is thrown twenty times. The probability that on the tenth throw the fourth six appears is -Maths 9th

Description : A fair dice is thrown twenty times. The probability that on the tenth throw the fourth six appears is -Maths 9th

Last Answer : (c) \(rac{84 imes5^6}{6^{10}}\)In the first nine throws we should have three sixes and six non-sixes and a six in the tenth throw and thereafter whatever face appears, it doesn't matter. ∴ Required probability = 9C3 \(\bigg(rac{1} ... x 1 x 1 ............x 1 {10 times} = \(rac{84 imes5^6}{6^{10}}\).

A hollow sphere and a solid sphere of the same material and equal radii are heated to the same temperature. In this case, (A) The cooling rate will be the same for the two spheres and hence the two spheres will have equal temperatures at any instant (B) Both the spheres will emit equal amount of radiation per unit time in the beginning (C) Both will absorb equal amount of radiation from the surrounding in the beginning (D) Both (B) & (C)

Description : A hollow sphere and a solid sphere of the same material and equal radii are heated to the same temperature. In this case, (A) The cooling rate will be the same for the two spheres and hence the ... equal amount of radiation from the surrounding in the beginning (D) Both (B) & (C)

Last Answer : (D) Both (B) & (C)

Find the value of 7plus root five ÷by seven minus root five minus seven minus root five ÷by seven plus root five equals to a+7÷11root five b -Maths 9th

Description : Find the value of 7plus root five ÷by seven minus root five minus seven minus root five ÷by seven plus root five equals to a+7÷11root five b -Maths 9th

Last Answer : This answer was deleted by our moderators...

Side AC of a right triangle ABC is divided into 8 equal parts. Seven line segments parallel to BC are drawn to AB from the points of division. -Maths 9th

Description : Side AC of a right triangle ABC is divided into 8 equal parts. Seven line segments parallel to BC are drawn to AB from the points of division. -Maths 9th

Last Answer : answer:

Twenty seven ducks are going to the pond. Five of them got lost, thirteen of them are staying home, nine of them are at the pond.Where are the rest of them -Riddles

Description : Twenty seven ducks are going to the pond. Five of them got lost, thirteen of them are staying home, nine of them are at the pond.Where are the rest of them -Riddles

Last Answer : There aren't any anywhere else

What is six and twenty seven hundred as a decimal and fraction?

Description : What is six and twenty seven hundred as a decimal and fraction?

Last Answer : It is 2706, which is an integer, not a fraction.

Is three a factor of twenty seven?

Description : Is three a factor of twenty seven?

Last Answer : Need answer

How do you write twenty-seven thousandths in decimal?

Description : How do you write twenty-seven thousandths in decimal?

Last Answer : If you mean 27/1000 then it is 0.027 as a decimal

What is six and twenty seven hundred as a decimal and fraction?

Description : What is six and twenty seven hundred as a decimal and fraction?

Last Answer : It is 2706, which is an integer, not a fraction.

How do you write seven hundred twenty-five trillion one hundred sixty-three billion five million three hundred thousand two hundred forty-nine?

Description : How do you write seven hundred twenty-five trillion one hundred sixty-three billion five million three hundred thousand two hundred forty-nine?

Last Answer : 725163005300249

twenty - two and eighty-seven thousandths ?

Description : twenty - two and eighty-seven thousandths ?

Last Answer : Answers is the place to go to get the answers you need and to ask the questions you want

The minimum number of members required for registration of a cooperative society are– (A) Two (B) Seven (C) Ten (D) Twenty

Description : The minimum number of members required for registration of a cooperative society are– (A) Two (B) Seven (C) Ten (D) Twenty

Last Answer : Answer: Ten

An iron sphere of mass 10 kg has the same diameter as an aluminium sphere of mass is 3.5 kg. Both spheres are dropped simultaneously from a tower. When they are l0 m above the ground, they have the same. -Physics

Description : An iron sphere of mass 10 kg has the same diameter as an aluminium sphere of mass is 3.5 kg. Both spheres are dropped simultaneously from a tower. When they are l0 m above the ground, they have the same. -Physics

Last Answer : (a) acceleration

The circumference of the base of 9 m high wooden solid cone is 44 m. Find the slant height of the cone. -Maths 9th

Description : The circumference of the base of 9 m high wooden solid cone is 44 m. Find the slant height of the cone. -Maths 9th

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

How many balls, each of radius 2 cm can be made from a solid sphere of lead of radius 8 cm ? -Maths 9th

Description : How many balls, each of radius 2 cm can be made from a solid sphere of lead of radius 8 cm ? -Maths 9th

Last Answer : No.of balls = Volume of share / Volume of each ball = 4 / 3π × 8 × 8 × 8 / 4 / 3π × 2 × 2 × 2 = 64

The circumference of the base of 9 m high wooden solid cone is 44 m. Find the slant height of the cone. -Maths 9th

Description : The circumference of the base of 9 m high wooden solid cone is 44 m. Find the slant height of the cone. -Maths 9th

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

How many balls, each of radius 2 cm can be made from a solid sphere of lead of radius 8 cm ? -Maths 9th

Description : How many balls, each of radius 2 cm can be made from a solid sphere of lead of radius 8 cm ? -Maths 9th

Last Answer : No.of balls = Volume of share / Volume of each ball = 4 / 3π × 8 × 8 × 8 / 4 / 3π × 2 × 2 × 2 = 64

Find the amount of water displaced by a solid spherical ball of diameter 4.2 cm, when it is completely immersed in water. -Maths 9th

Description : Find the amount of water displaced by a solid spherical ball of diameter 4.2 cm, when it is completely immersed in water. -Maths 9th

Last Answer : The amount of water displaced by a solid spherical ball when it is completely immersed in water is equal to its volume. Volume of a sphere of radius r is 34​πr3 As the diameter of the ball is 4.2 cm, its radius r=2.1 cm Hence, volume of water displaced =34​πr3=34​×722​×2.1×2.1×2.1=38.808 cm3

Find the amount of water displaced by a solid spherical ball of diameter 4.2 cm, when it is completely immersed in water. -Maths 9th

Description : Find the amount of water displaced by a solid spherical ball of diameter 4.2 cm, when it is completely immersed in water. -Maths 9th

Last Answer : Solution of this question

A solid cube of side 12 cm is cut into -Maths 9th

Description : A solid cube of side 12 cm is cut into -Maths 9th

Last Answer : Volume of given cube = a3 = 123 = 12 x 12 x 12 cm3 Let the edge of the new cube = x ∴ Volume of new cube = x3 Volume of 8 new cubes = 8x3 Now, 8x3 = 12 x 12 x 12 ⇒ x 3 = 12 x 12 x 12/8 = 6 3 ⇒ x ... area of new cubes = 6a2/6x2 = 6 x 122/6 x 62 = 6 x 12 x 12/6 x 6 x 6 = 4/1 = 4 : 1

A solid cylinder has total surface area of 462 cm square. -Maths 9th

Description : A solid cylinder has total surface area of 462 cm square. -Maths 9th

Last Answer : Let r cm be the radius of the base and h cm be the height of the cylinder, Then, total surface area of cylinder = 2 πr (r + h) Curved surface area of cylinder = 2 πrh We have, Curved surface area = 1/3(Total surface ... x 22 = 7/2 cm Volume of the cylinder = πr2h = 22/7 x 7 x 7 x 7/2 = 539 cm3

A right DABC with sides 5 cm, 12 cm and 13 cm is revolved about the side 12 cm. What is the volume of the solid so obtained ? -Maths 9th

Description : A right DABC with sides 5 cm, 12 cm and 13 cm is revolved about the side 12 cm. What is the volume of the solid so obtained ? -Maths 9th

Last Answer : From the figure it is clear that a cone is formed. Here, h = 12 cm, r = 5 cm Volume of cone = = 314 cm3

An equilateral triangle with side a is revolved about one of its sides as axis. What is the volume of the solid of revolution thus obtained ? -Maths 9th

Description : An equilateral triangle with side a is revolved about one of its sides as axis. What is the volume of the solid of revolution thus obtained ? -Maths 9th

Last Answer : answer:

The diameter of a solid mettalic right circular cylinder is equal to its height. After culting out the largest possible solid sphere -Maths 9th

Description : The diameter of a solid mettalic right circular cylinder is equal to its height. After culting out the largest possible solid sphere -Maths 9th

Last Answer : answer:

A right circular solid cone of maximum possible volume is cut off from a solid metallic right circular cylinder of volume V. -Maths 9th

Description : A right circular solid cone of maximum possible volume is cut off from a solid metallic right circular cylinder of volume V. -Maths 9th

Last Answer : answer:

A solid right circular cylinder of radius 8 cm and height 2 cm is melted and cast into a right circular cone of height 3 times that of the cylinder. -Maths 9th

Description : A solid right circular cylinder of radius 8 cm and height 2 cm is melted and cast into a right circular cone of height 3 times that of the cylinder. -Maths 9th

Last Answer : Height of cone = 3 times height of cylinder = 3 3 = 9 cm Volume of cylinder = volume of cone r2 = 8 8 r = 8 cm l2 = h2 + r2 = (9)2 + (8)2 l = = 12 cm C.S.A (cone) = = 301.71 cm2

The volume of a certain rectangular solid is 8 cm^3. Its total surface area is 32 cm^2 and its three dimensions are in geometric progression. -Maths 9th

Description : The volume of a certain rectangular solid is 8 cm^3. Its total surface area is 32 cm^2 and its three dimensions are in geometric progression. -Maths 9th

Last Answer : (b) 32 Let the edges of the solid be a, ar, ar2. Then, Volume = a x ar x ar2 = a3r3 = (ar)3. Given (ar)3 = 8 ⇒ ar = 2 Also, surface area = 2(a x ar + ar x ar2 + a × ar2) = 2(a2r + ... Given, 2ar (a + ar + ar2) = 32 ⇒ 4(a + ar + ar2) = 32 ; Sum of lengths of all edges = 32.

Rinku has built a cuboidal water tank in his house. The top of the water tank is covered with an iron lid. -Maths 9th

Description : Rinku has built a cuboidal water tank in his house. The top of the water tank is covered with an iron lid. -Maths 9th

Last Answer : Total inner surface area of the water tank including the base without top = 2(l + b) h + l b = 2(180 + 120) 60 + 180 120 = 36000 + 21600 = 57600 cm2 Area of each title = 10 ... 57600 / 80 = 720 Total amount required for 720 tiles at the rate of 480 per dozen = 480 / 12 720 = 28800

Rinku has built a cuboidal water tank in his house. The top of the water tank is covered with an iron lid. -Maths 9th

Description : Rinku has built a cuboidal water tank in his house. The top of the water tank is covered with an iron lid. -Maths 9th

Last Answer : Total inner surface area of the water tank including the base without top = 2(l + b) h + l b = 2(180 + 120) 60 + 180 120 = 36000 + 21600 = 57600 cm2 Area of each title = 10 ... 57600 / 80 = 720 Total amount required for 720 tiles at the rate of 480 per dozen = 480 / 12 720 = 28800

A hemispherical tank is made up of an iron -Maths 9th

Description : A hemispherical tank is made up of an iron -Maths 9th

Last Answer : Inner radius of the hemispherical tank (r) = 1 m Outer radius of the hemispherical tank (R) = 1 + 0.01 = 1.01 m Volume of iron used to make the hemispherical tank = 2/3 πR3 - 2/3πr3 = 2/3π(R3 - r3) = 2/3 x 22/7 [(1.01)3 - 13] = 44/21(1.0303 - 1) = 44/21 x 0.0303 = 0.06349 m3

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 meter , sheet being 2 m wide. -Maths 9th

Description : 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 meter , sheet being 2 m wide. -Maths 9th

Last Answer : This answer was deleted by our moderators...

A cylindrical rod of iron whose height is eight times its radius is melted and cast into spherical balls each of half the radius of the cylinder. -Maths 9th

Description : A cylindrical rod of iron whose height is eight times its radius is melted and cast into spherical balls each of half the radius of the cylinder. -Maths 9th

Last Answer : Let radius of iron rod = r ∴∴ Height = 8r ∴∴ Volume of iron rod =π×(r)2×8r⇒8πr3=π×(r)2×8r⇒8πr3 ⇒⇒ Radius of spherical ball =r2=r2 Volume of spherical ball =43π(r2)3=43π(r2)3 Let n balls are casted ∴n×43π(r38)=8πr3∴n×43π(r38)=8πr3 ⇒n6=8⇒n=48

A cylindrical rod of iron whose radius is one-fourth of its height is melted and cast into spherical balls of the same radius as that of the cylinder. -Maths 9th

Description : A cylindrical rod of iron whose radius is one-fourth of its height is melted and cast into spherical balls of the same radius as that of the cylinder. -Maths 9th

Last Answer : Let radius of cylindrical rod =r ⇒ height =4r Volume of cylindrical rod =πr2h =πr2(4r) =4πr3 Volume of spherical balls of radius r=34​πr3 No. of balls =34​πr34πr3​=

A spherical iron shell with external diameter 21 cm weighs 22775 x 5/21 grams. Find the thickness of the shell if the metal weighs 10 gms per cu cm. -Maths 9th

Description : A spherical iron shell with external diameter 21 cm weighs 22775 x 5/21 grams. Find the thickness of the shell if the metal weighs 10 gms per cu cm. -Maths 9th

Last Answer : answer:

Are marbles considered circles or spheres?

Description : Are marbles considered circles or spheres?

Last Answer : Spheres, they’re three dimensional. Circles are two dimensional, FLAT.

Are spheres natures goto storage shape?

Description : Are spheres natures goto storage shape?

Last Answer : answer:Of all the solids having a given volume, the sphere is the one with the smallest surface area; of all solids having a given surface area, the sphere is the one having the greatest volume. ... prisms and there would be wasted storage space if we tried to fit square boxes into round cars.

What are those large red spheres sometimes found on power lines?

Description : What are those large red spheres sometimes found on power lines?

Last Answer : so planes, hang-gliders, etc don’t hit them. makes them more visible against the ground-scape.

What is the answer. There are three identical metal spheres labeled A, B and A has a charge of 1C while B and Care neutral. If A touches B and then is removed, and then B touches C and is removed what is the charge on C?

Description : What is the answer. There are three identical metal spheres labeled A, B and A has a charge of 1C while B and Care neutral. If A touches B and then is removed, and then B touches C and is removed what is the charge on C?

Last Answer : C are***

which of earths spheres is most likely to be involved in a landslide?

Description : which of earths spheres is most likely to be involved in a landslide?

Last Answer : The Lithosphere.

What importance did spheres of influence have for china and for the nations involved?

Description : What importance did spheres of influence have for china and for the nations involved?

Last Answer : Need answer