Find the radius and height of the conical tent if the base area of the...
Find the radius and height of the conical tent if the base area of the...
Given:
- Base area of the tent = 154 cm^2
- Covered surface area of the tent = 396 cm^2
To find:
- Radius and height of the conical tent
Formula:
- The formula for the base area of a cone is A = πr^2, where A is the base area and r is the radius.
- The formula for the surface area of a cone is SA = πr(r + l), where SA is the surface area, r is the radius, and l is the slant height.
Solution:
1. Calculating the radius:
Given that the base area of the tent is 154 cm^2, we can use the formula A = πr^2 to find the radius.
154 = πr^2
To solve for r, divide both sides of the equation by π:
154/π = r^2
Take the square root of both sides to find the radius:
√(154/π) = r
Therefore, the radius of the conical tent is √(154/π).
2. Calculating the slant height:
Given that the covered surface area of the tent is 396 cm^2, we can use the formula SA = πr(r + l) to find the slant height.
396 = πr(r + l)
Since we have already found the value of r, we can substitute it into the equation:
396 = π(√(154/π))(√(154/π) + l)
Simplify the equation:
396 = π(154/π + l)
Distribute π to both terms inside the parentheses:
396 = 154 + πl
Rearrange the equation to isolate l:
πl = 396 - 154
l = (396 - 154)/π
Therefore, the slant height of the conical tent is (396 - 154)/π.
3. Calculating the height:
To find the height of the conical tent, we can use the Pythagorean theorem.
The height, radius, and slant height form a right triangle.
Using the equation a^2 + b^2 = c^2, where a and b are the legs of the right triangle and c is the hypotenuse (slant height), we can substitute the known values:
h^2 + r^2 = l^2
Substitute the values of r and l:
h^2 + (√(154/π))^2 = [(396 - 154)/π]^2
Simplify the equation:
h^2 + 154/π = [(396 - 154)/π]^2
Multiply both sides by π:
πh^2 + 154 = (396 - 154)^2
Simplify the equation:
πh^2 + 154 = 242^2
Rearrange the equation to isolate h:
πh^2 = 242^2 - 154
h^2 = (242^2 - 154)/π
h = √[(242^2 - 154)/π]
Therefore, the height of the conical tent is √[(242^2 - 154)/π].
Conclusion:
The radius of the con
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