Advertisements
Advertisements
Question
Find the volume of a right circular cone with:
height 21 cm and slant height 28 cm.
Solution
From the relation
`l^2=r^2+h^2,`we have
`r=sqrt(l^2-h^2)=sqrt((28)^2)-(21)^2=7sqrt7cm`
So, volume of cone =`1/3xxpir^2xxh`
`=1/3xx22/7xx(21)^2xx(7sqrt7)^2`
`=7546cm^3`
APPEARS IN
RELATED QUESTIONS
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.
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 heap of wheat is in the form of a cone of diameter 9 m and height 3.5 m. Find its volume. How much canvas cloth is required to just cover the heap? (Use ЁЭЬЛ = 3.14).
A conical pit of top diameter 3.5 m is 12 m deep. What is its capacity in kilo litres?
The cross-section of a railway tunnel is a rectangle 6 m broad and 8 m high surmounted by a semi-circle as shown in the figure. The tunnel is 35 m long. Find the cost of plastering the internal surface of the tunnel (excluding the floor) at the rate of Rs. 2.25 per m2.
A solid is in the form of a right circular cone mounted on a hemisphere. The diameter of the base of the cone, which exactly coincides with hemisphere, is 7 cm and its height is 8 cm. The solid is placed in a cylindrical vessel of internal radius 7 cm and height 10 cm. How much water, in cm3, will be required to fill the vessel completely?
Surface area of a cone is 188.4 sq.cm and its slant height is 10 cm. Find its perpendicular height ( π= 3.14)
The curved surface area of a right circular cone of radius 11.3 cm is 710 cm2. What is the slant height of the cone ?
The volume of a conical tent is 1232 m3 and the area of the base floor is 154 m2. Calculate the: height of the tent.
The surface area of a solid sphere is increased by 21% without changing its shape. Find the percentage increase in its: volume