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Keep the radius the same but use a different height is the volume of the sphere 2/3 the volume of the cylinder now explain your answer

User Soheil Pourbafrani
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1 Answer

19 votes
19 votes

From geometry, we know that:

• the volume of a sphere of radius r is:


V_S=(4)/(3)\cdot\pi\cdot r^3,

• the volume of a cylinder of radius r and heigth h is:


V_C=h\cdot\pi\cdot r^2.

If the volume of the sphere (Vs) is 2/3 the volume of the cylinder (Vc), we have:


\begin{gathered} V_S=(2)/(3)\cdot V_C, \\ (4)/(3)\cdot\pi\cdot r^3=(2)/(3)\cdot h\cdot\pi\cdot r^2. \end{gathered}

Solving for h, we find that:


h=2r.

We have found that the height of the cylinder is two times its radius.

Answer

• We have a sphere and cylinder with the same radius.

,

• We know that the volume of the sphere is


V_S=(2)/(3)\cdot V_C.

• By replacing the formulas of each volume, we find that the heigh of the cylinder is:


h=2r.

User Viktorija
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