To find the volume of a solid composed of a cone standing on a hemisphere, where both have a radius of 1 cm and the height of the cone is also 1 cm, we calculate the volumes of the cone and the hemisphere separately and then add them.
The volume of a cone is given by (1/3)πr²h. With r = 1 cm and h = 1 cm, the volume of the cone is (1/3)π × 1² × 1 = (1/3)π cm³.
The volume of a hemisphere is half the volume of a sphere, which is
(2/3)πr³. With r = 1 cm, the volume of the hemisphere is (2/3) π × 1³ = (2/3) π cm³.
Adding these, the total volume of the solid is (1/3) π + (2/3) π = π cm³. This represents the volume of the solid in terms of π.

A solid is in the shape of a cone standing on a hemisphere with both their radii being equal to 1 cm and the height of the cone is equal to its radius. Find the volume of the solid in terms of pi.

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Introduction to Composite Geometric Shapes

The calculation of the volume of a solid composed of a cone standing on a hemisphere is a classic problem in geometry that demonstrates how to deal with composite shapes. This problem is not just a theoretical exercise in spatial reasoning; it has practical applications in fields such as design and engineering. In this case, both the cone and the hemisphere have a radius of 1 cm, and the height of the cone is also 1 cm. Understanding how to calculate the volume of such a composite shape requires a clear grasp of the formulas for the volumes of individual shapes and how these volumes combine.

Understanding the Cone’s Volume

The first step in solving this problem is to calculate the volume of the cone. The formula for the volume of a cone is (1/3)πr²h, where r is the radius and h is the height. In our case, both the radius and the height of the cone are 1 cm. This simplifies the calculation, as squaring the radius (1 cm) and multiplying by the height (1 cm) results in the same value. The volume of the cone thus becomes (1/3)×1²×1 = (1/3)π cm³.

Calculating the Hemisphere’s Volume

Next, we calculate the volume of the hemisphere. The volume of a hemisphere is half the volume of a sphere, which is given by (4/3)​πr³. Therefore, the volume of the hemisphere is (2/3)πr³. With a radius of 1 cm, the calculation simplifies to (2/3)π×1³ = (2/3)π cm³. This step is crucial as it gives us the volume of the lower half of our composite solid, which is the base upon which the cone stands.

Total Volume of the Composite Solid
To find the total volume of the composite solid, we add the volumes of the cone and the hemisphere. The sum of (1/3) π cm³ (the volume of the cone) and (2/3)π cm³ (the volume of the hemisphere) gives us the total volume. This addition is straightforward since both volumes are expressed in terms of π, facilitating easy calculation. The total volume of the solid is thus (1/3)π + (2/3)π = π cm³.

Practical Implications of the Calculation

This calculation has practical implications in various fields. For instance, in manufacturing and design, understanding the volume of composite shapes is crucial for material estimation, cost calculation, and design efficiency. This problem exemplifies how geometric principles are applied in real-world scenarios, bridging the gap between theoretical mathematics and practical application. It highlights the importance of precision and accuracy in calculations, which are essential in these fields.

The Elegance of Geometric Calculations

In conclusion, the process of calculating the volume of a solid composed of a cone on a hemisphere demonstrates the elegance and utility of geometric calculations. This exercise reinforces the understanding of how to deal with composite shapes and the importance of accurate calculations in practical applications. It showcases the beauty of geometry in solving complex problems and its relevance in everyday practical situations. This problem-solving approach is not just about numbers and formulas; it’s about understanding the spatial properties of objects and their applications in the real world.

Discuss this question in detail or visit to Class 10 Maths Chapter 12 for all questions.
Questions of 10th Maths Exercise 12.2 in Detail

A solid is in the shape of a cone standing on a hemisphere with both their radii being equal to 1 cm and the height of the cone is equal to its radius. Find the volume of the solid in terms of π.
Rachel, an engineering student, was asked to make a model shaped like a cylinder with two cones attached at its two ends by using a thin aluminium sheet. The diameter of the model is 3 cm and its length is 12 cm. If each cone has a height of 2 cm, find the volume of air contained in the model that Rachel made.
A gulab jamun, contains sugar syrup up to about 30% of its volume. Find approximately how much syrup would be found in 45 gulab jamuns, each shaped like a cylinder with two hemispherical ends with length 5 cm and diameter 2.8 cm.
A pen stand made of wood is in the shape of a cuboid with four conical depressions to hold pens. The dimensions of the cuboid are 15 cm by 10 cm by 3.5 cm. The radius of each of the depressions is 0.5 cm and the depth is 1.4 cm. Find the volume of wood in the entire stand.
A vessel is in the form of an inverted cone. Its height is 8 cm and the radius of its top, which is open, is 5 cm. It is filled with water up to the brim. When lead shots, each of which is a sphere of radius 0.5 cm are dropped into the vessel, one-fourth of the water flows out. Find the number of lead shots dropped in the vessel.
A solid iron pole consists of a cylinder of height 220 cm and base diameter 24 cm, which is surmounted by another cylinder of height 60 cm and radius 8 cm. Find the mass of the pole, given that 1 cm³ of iron has approximately 8g mass.
A solid consisting of a right circular cone of height 120 cm and radius 60 cm standing on a hemisphere of radius 60 cm is placed upright in a right circular cylinder full of water such that it touches the bottom. Find the volume of water left in the cylinder, if the radius of the cylinder is 60 cm and its height is 180 cm.
A spherical glass vessel has a cylindrical neck 8 cm long, 2 cm in diameter; the diameter of the spherical part is 8.5 cm. By measuring the amount of water it holds, a child finds its volume to be 345 cm³. Check whether she is correct, taking the above as the inside measurements, and π = 3.14.