Advertisements
Advertisements
प्रश्न
The internal and external diameters of a hollow hemi-spherical vessel are 21 cm and 28 cm respectively. Find: external curved surface area .
उत्तर
External radius (R) = 14 cm
Internal radius (r) =`21/2` cm
External curved surface area =
`2piR^2`
=`2xx22/7xx14xx14`
=`1232 "cm"^2`
APPEARS IN
संबंधित प्रश्न
The radius of a cone is 5 cm and vertical height is 12 cm. Find the area of the curved surface.
The height of a cone is 21 cm. Find the area of the base if the slant height is 28 cm.
Find the ratio of the curved surface areas of two cones if their diameters of the bases are equal and slant heights are in the ratio 4 : 3.
There are two cones. The curved surface area of one is twice that of the other. The slant height of the later is twice that of the former. Find the ratio of their radii.
The diameters of two cones are equal. If their slant heights are in the ratio 5 : 4, find the ratio of their curved surfaces.
A cylinder and a cone have equal radii of their bases and equal heights. If their curved surface areas are in the ratio 8:5, show that the radius of each is to the height of each as 3:4.
Find the volume of a right circular cone with:
radius 3.5 cm, height 12 cm
Two cones have their heights in the ratio 1 : 3 and the radii of their bases in the ratio 3 : 1. Find the ratio of their volumes.
A conical pit of top diameter 3.5 m is 12 m deep. What is its capacity in kilo litres?
Find what length of canvas, 1.5 m in width, is required to make a conical tent 48 m in diameter and 7 m in height. Given that 10% of the canvas is used in folds and stitchings. Also, find the cost of the canvas at the rate of Rs. 24 per metre.
A solid cone of height 8 cm and base radius 6 cm is melted and recast into identical cones, each of height 2 cm and diameter 1 cm. Find the number of cones formed.
A solid metal sphere is cut through its center into 2 equal parts. If the diameter of the sphere is `3 1/2 cm`, find the total surface area of each part correct to two decimal places.
The given figure shows the cross section of a water channel consisting of a rectangle and a semi-circle. Assuming that the channel is always full, find the volume of water discharged through it in one minute if water is flowing at the rate of 20 cm per second. Give your answer in cubic metres correct to one place of decimal.
Find the radius of the circular base of the cone , if its volume is 154 cm3 and the perpendicular height is 12 cm
Find the curved surface area of a cone whose height is 8 cm and base diameter is 12 cm .
A buoy is made in the form of a hemisphere surmounted by a right circular cone whose circular base coincides with the plane surface of the hemisphere. The radius of the base of the cone is 3.5 m and its volume is two-third the volume of hemisphere. Calculate the height of the cone and the surface area of the buoy, correct to two decimal places.
The volume of a conical tent is 1232 m3 and the area of the base floor is 154 m2. Calculate the: length of the canvas required to cover this conical tent if its width is 2 m.
The given figure shows the cross-section of a cone, a cylinder and a hemisphere all with the same diameter 10 cm and the other dimensions are as shown. Calculate: the density of the material if its total weight is 1.7 kg
The ratio of the radii of two right circular cones of the same height is 1 : 3. Find the ratio of their curved surface area when the height cone is 3 times the radius of the smaller cone.
The curved surface area of a right circular cone of height 15 cm and base diameter 16 cm is
