Advertisements
Advertisements
प्रश्न
The height of a circular cylinder is 20 cm and the radius of its base is 7 cm. Find :
- the volume
- the total surface area.
उत्तर
For circular cylinder,
Height = h = 20 cm
Radius of the base = r = 7 cm
i. Volume of a cylinder = πr2h
= `22/7 xx 7 xx 7 xx 20 cm^3`
= 3080 cm3
ii. Total surface area of a cylinder = 2πr(h + r)
= `2 xx 22/7 xx 7(20 + 7) cm^2`
= 2 × 22 × 27 cm2
= 1188 cm2
APPEARS IN
संबंधित प्रश्न
The capacity of a closed cylindrical vessel of height 1 m is 15.4 litres. How many square metres of metal sheet would be needed to make it?
`["Assume "pi=22/7]`
A circus tent is cylindrical to a height of 8 m surmounted by a conical part. If total height of the tent is 13 m and the diameter of its base is 24 m; calculate :
- total surface area of the tent,
- area of canvas, required to make this tent allowing 10% of the canvas used for folds and stitching.
A cylinder of circumference 8 cm and length 21 cm rolls without sliding for `4 1/2` seconds at the rate of 9 complete rounds per second. Find the area covered by the cylinder in `4 1/2` seconds.
3080 cm3 of water is required to fill a cylindrical vessel completely and 2310 cm3 of water is required to fill it upto 5 cm below the top. Find :
- radius of the vessel.
- height of the vessel.
- wetted surface area of the vessel when it is half-filled with water.
A cylindrical vessel of height 24 cm and diameter 40 cm is full of water. Find the exact number of small cylindrical bottles, each of height 10 cm and diameter 8 cm, which can be filled with this water.
Find the weight of a lead pipe 35 cm long. The external diameter of the pipe is 2.4 cm and the thickness of the pipe is 2mm, given 1 cm3 of lead weighs 10 gm.
A conical container is fully filled with petrol. The radius is 10 m and the height is 15 m. If the container can release the petrol through its bottom at the rate of 25 cu. meter per minute, in how many minutes the container will be emptied. Round off your answer to the nearest minute.
A cylindrical tube opened at both the ends is made of iron sheet which is 2 cm thick. If the outer diameter is 16 cm and its length is 100 cm, find how many cubic centimeters of iron has been used in making the tube?
The water for a factory is stored in a hemispherical tank whose internal diameter is 14 m. The tank contains 50 kilolitres of water. Water is pumped into the tank to fill to its capacity. Calculate the volume of water pumped into the tank.
The volume of a cylinder which exactly fits in a cube of side a is ______.
