An inverted right circular cone has a radius of 9 cm. This cone is par...
Given,
Surface area of oil = 36 π = πr2
⇒ r = 6 cm
Now,
∆ABC ~ ∆AED

h = 6 cm
∴ Volume of oil in the cone = (1/3)πr
2h
= (1/3)π6
2 x 6
= 72π
⇒ Time taken = 72π/1
= 72π hours.
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An inverted right circular cone has a radius of 9 cm. This cone is par...
To find the height of the cone, we can use the formula for the volume of a cone:
V = (1/3)πr^2h
where V is the volume, r is the radius, and h is the height.
Since the cone is partly filled with oil up to a level 3 cm from the top, the height of the oil is the total height of the cone minus 3 cm.
So, h = total height - 3 cm
To find the total height, we can use the formula for the surface area of a cone:
A = πr(r + √(r^2 + h^2))
where A is the surface area.
Since the surface area is given as 36 cm^2, we can substitute the values into the equation:
36 = π(9)(9 + √(9^2 + h^2))
Now we can solve for h:
36/π = 81 + √(81 + h^2)
36/π - 81 = √(81 + h^2)
(36/π - 81)^2 = 81 + h^2
h^2 = (36/π - 81)^2 - 81
h = √((36/π - 81)^2 - 81)
Using a calculator, we find that h ≈ 6.81 cm.
Therefore, the height of the cone is approximately 6.81 cm.
An inverted right circular cone has a radius of 9 cm. This cone is par...
Given,
Surface area of oil = 36 π = πr2
⇒ r = 6 cm
Now,
∆ABC ~ ∆AED

h = 6 cm
∴ Volume of oil in the cone = (1/3)πr
2h
= (1/3)π6
2 x 6
= 72π
⇒ Time taken = 72π/1
= 72π hours.