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If the total surface area of a hemispher...

If the total surface area of a hemisphere is `27 pi` square cm, then the radius of the base of the hemisphere is.
यदि किसी गोलार्द्ध का कुल पृष्ठीय क्षेत्रफल 277 वर्ग सेमी. है, तो गोलार्द्ध के आधार की त्रिज्या है -
A)9 सेमी.
B)`9sqrt(3)` सेमी.
C)3 सेमी.
D)`3sqrt(5)` सेमी.

A

9 सेमी.

B

`9sqrt(3)` सेमी.

C

3 सेमी.

D

`3sqrt(5)` सेमी.

Text Solution

AI Generated Solution

The correct Answer is:
To find the radius of the base of a hemisphere given that its total surface area is \(27\pi\) square cm, we can follow these steps: ### Step 1: Understand the formula for the total surface area of a hemisphere. The total surface area \(A\) of a hemisphere is given by the formula: \[ A = 3\pi r^2 \] where \(r\) is the radius of the base of the hemisphere. ### Step 2: Set up the equation with the given total surface area. According to the problem, the total surface area is \(27\pi\) square cm. Therefore, we can set up the equation: \[ 3\pi r^2 = 27\pi \] ### Step 3: Simplify the equation. We can divide both sides of the equation by \(\pi\) (since \(\pi\) is a common factor and not equal to zero): \[ 3r^2 = 27 \] ### Step 4: Solve for \(r^2\). Next, we divide both sides by 3: \[ r^2 = \frac{27}{3} = 9 \] ### Step 5: Find the radius \(r\). Now, we take the square root of both sides to find \(r\): \[ r = \sqrt{9} = 3 \text{ cm} \] ### Conclusion: The radius of the base of the hemisphere is \(3\) cm. ### Answer: The correct option is C) \(3\) cm. ---

To find the radius of the base of a hemisphere given that its total surface area is \(27\pi\) square cm, we can follow these steps: ### Step 1: Understand the formula for the total surface area of a hemisphere. The total surface area \(A\) of a hemisphere is given by the formula: \[ A = 3\pi r^2 \] where \(r\) is the radius of the base of the hemisphere. ...
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