Question

एक शंकु के छिन्नक, जो 45 cm ऊंचा है, के सिरों की त्रिज्याएँ 28 cm और 7 cm है इसका आयतन वक्र पृष्ठीय क्षेत्रफल और संपूर्ण पृष्ठीय क्षेत्रफल ज्ञात कीजिए

Answer 1

The volume of frustum of a right circular cone is 48490.5 cm³. The lateral surface area of frustum is 5460.27 cm². The lateral surface area of frustum is 8077.22 cm².

Step-by-step explanation:

शंकु के छिन्नक = Frustum of a right circular cone

Given information:

Height of Frustum (h) = 45 cm

Radius of upper base (r)= 7 cm

Radius of lower base (R)= 28 cm

Volume of frustum of a right circular cone is

$Volume=\frac{1}{3}\pi h(r^2+rR+R^2)$

Substitute the given values in the above formula.

$Volume=\frac{1}{3}\pi (45)((7)^2+(7)(28)+(28)^2)$

$Volume=48490.4826$

$Volume\approx 48490.5$

The volume of frustum of a right circular cone is 48490.5 cm³.

Lateral surface area of frustum of a right circular cone is

$L=\pi(r+R)\sqrt{(R-r)^2+h^2}$

Substitute the given values in the above formula.

$L=\pi(7+28)\sqrt{(28-7)^2+(45)^2}$

$L=5460.27421$

$L\approx 5460.27$

Therefore, the lateral surface area of frustum is 5460.27 cm².

Total surface area of frustum of a right circular cone is

$S=\pi(r+R)\sqrt{(R-r)^2+h^2}+\pi r^2+\pi R^2$

$S=\pi(7+28)\sqrt{(28-7)^2+(45)^2}+\pi (7)^2+\pi (28)^2$

$S\approx 8077.22$

Therefore, the lateral surface area of frustum is 8077.22 cm².

#Learn more

Volume and area of frustum : https://brainly.in/question/12661215

Volume of frustum : https://brainly.in/question/12661219

Answer 2

Answer:

S = 8077. 22

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