Question

Find the volume and the total surface area of a hemisphere of radius 3.5 cm.​

Answer 1

Answer:

$\bigstar{Volume\:=89.83\:cm^{3} }$

$\bigstar{Total\:surface\:Area\:=\:115.5\:cm^{2} }$

Step-by-step explanation:

Given:

• Radius of the hemisphere = 3.5cm

To Find:

• Volume of the hemisphere
• Total Surface Area of hemisphere

Solution:

Volume of hemisphere:

→ Volume of hemisphere is given by the equation,

   Volume=(2/3)×π×r³

   where r is the radius of the hemisphere

→ Substituting the given datas we get,

   Volume=(2/3)×22/7×(3.5)³

   $\boxed{Volume\:=\:89.83\:cm^{3} }$

Total surface area of hemisphere:

→ Total surface area of a hemisphere is given by the equation

   Total Surface Area = 3πr²

→ Substituting the given datas in the equation, we get

   Total Surface Area = 3×(22/7)×(3.5)²

   $\boxed{Total\:Surface\:Area\:=\:115.5cm^{2} }$

   

Notes:

• Volume of a hemisphere = (2/3)πr³
• Total Surface area of a hemisphere = 3πr²
• Curved Surface area of a hemisphere = 2πr²

Answer 2

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Given,

Radius of sphere = 3.5 = 7/2

$volume \: of \: sphere \: = \frac{2}{3} \pi \: {r}^{3} \\ \\ = \frac{2}{3} \times \frac{22}{7} \times \frac{7}{2} \times \frac{7}{2} \times \frac{7}{2} \\ \\ = \frac{539}{6} \\ \\ = 89.83 {cm}^{3} \\ \\ surface \: area \: = 3\pi \: {r}^{2} \\ \\ = 3 \times \frac{22}{7} \times \frac{7}{2} \times \frac{7}{2} \\ \\ = \frac{231}{2} \\ \\ = 115.5 {cm}^{2}$