Volume of two hemispheres are in the ratio 64:27

  • Surface Areas and Volumes

Volume of two hemispheres are in the ratio 64:27

Volume of sphere = 4/3*pie*r3

let the radius of the first sphere be 'R'

let the radius of the second sphere be 'r'As per the question,(4/3*pie*R3) / (4/3*pie*r3) = 64 / 27= R3/ r3= 64 / 27= R / r = 4 / 3 - - - - - - - (1)Now, CSA of a sphere = 4*pie*r2Ratio of CSA's of the two spheres is:(4*pie*R2) / (4*pie*r2)R2/ r2= (R / r)2Using (1)(R / r)2= (4/3)2=16 / 9Therefore, the ration of the CSA's of the two spheres is 16:9.Hope This Helps!!

Volume of two hemispheres are in the ratio 64:27

arghh! That thing is so messed up .-. Lemme try again!

Volume of sphere = 4/3*pie*r3

let the radius of the first sphere be 'R'

let the radius of the second sphere be 'r'As per the question,

As perthe question

Volume of two hemispheres are in the ratio 64:27
,

(4/3*pie*R3) / (4/3*pie*r3) = 64 / 27

= R3/ r3= 64 / 27= R / r = 4 / 3 - - - - - - - (1)

Now, CSA of a sphere = 4*pie*r2

Ratio of CSA's of the two spheres is:

(4*pie*R2) / (4*pie*r2)

R2/ r2= (R / r)2

Using (1)(R / r)2= (4/3)2=16 / 9

Therefore, the ratio of the CSA's of the two spheres is 16:9.

Hope

Volume of two hemispheres are in the ratio 64:27
This Helps!!

Volume of two hemispheres are in the ratio 64:27

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Given:

The ratio of the volume of the two spheres = 64 : 27

Formula used:

The volume of the sphere = (4/3) × π × R3

The surface area of the sphere = 4 × π × R2     Where R = The radius of the sphere

Calculation:

Let us assume the ratio of the surface area of the sphere be X : Y and the radius of the spheres be R1 and R2 respectively

  

Volume of two hemispheres are in the ratio 64:27

⇒ The volume of the first sphere = [(4/3) × π × R13]     ----(1)

⇒ The volume of the second cylinder = [(4/3) × π × R23]     ----(2)

⇒ According to the question equation (1) ÷ (2) = 64 : 27

⇒ (R1/R2)3 = 64/27

⇒ R1/R2 = ∛(64/27)

⇒ R1/R2 = 4/3

⇒ Let us assume the radius of the first sphere = 4x and the second sphere = 3x

⇒ The surface area of the first sphere = 4 × π × (4x)2 = 64πx2     ----(3)

⇒ The surface area of the second sphere = 4 × π × (3x)2 = 36πx2     ----(4)

⇒ The ratio of the surface of the spheres = (64πx2)/(36πx2)

⇒ The ratio of the surface area of the spheres = 16/9

⇒ The ratio of their surface area X : Y = 16 : 9

∴ The required result will be 16 : 9.

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Volume of two hemispheres are in the ratio 64:27

Text Solution

Solution : Let the radius of two spheres be `r_(1)` and `r_(2)` <br> Given, the ratio of the volume of two spheres = 64: 27 <br> `(V_(1))/(V_(2)) =(64)/(27) rArr ((4)/(3)pir_(1)^(3))/((4)/(3)pir_(2)^(3)) = (64)/(27)` <br> `rArr" "((r_(1))/(r_(2)))^(3) = ((4)/(3))^(3) " "[because "volume of sphere" =(4)/(3) pir^(3)]` <br> `rArr " "(r_(1))/(r_(2)) =(4)/(3)` <br> Let the surface areas of the two spheres `S_(1)` and `S_(2)` <br> `therefore" "(S_(1))/(S_(2)) = (4pir_(1)^(2))/( 4pir_(2)^(2)) = ((r_(1))/(r_(2)))^(2) rArr S_(1),S_(2) = ((4)/(3))^(2) = (16)/(9)` <br> `rArr" "S_(1),S_(2) = 16:9` <br> Hence, the ratio of the their surface areas is 16: 9.