Curved Surface area of a right circular cylinder

Q.

Find the cost of painting $15$ cylindrical pillars of a building at $Rs.2.50$ per square metre if the diameter and height of each pillar are $48cm$ and $7$ metres respectively.

Q.

A road roller takes 750 complete revolutions to move once over to level a road. Find the area of the road if the diameter of the road roller is 84 cm and its length is 1 m.

Q. Find the area of the sheet required to make a cylindrical container which is open at one side and whose diameter is 28 cm and height is 20 cm. Find the approximate area of the sheet required to make a lid of height 2 cm for this container.

Q. How much iron is needed to make a rod of length 90 cm and diameter 1.4 cm?

Q.

Find the total surface area of a closed cylindrical drum if its diameter is $50$ cm and height is $45$ cm. $(\pi =3.14)$

Q. Choose the correct pair.


(Here LSA - Lateral surface area, CSA - Curved surface area, TSA - Total surface area)

1. TSA of Cube
2. CSA of Cylinder
3. $2(lb+bh+hl)$
4. $2\pi r(h+r)$
5. $6a^2$
6. $4a^2$
7. $2\pi rh$
8. LSA of Cube
9. TSA of Cubiod
10. LSA of Cuboid
11. TSA of Cylinder
12. $2h(l+b)$

Q. Total surface area of a cylinder with radius 'r' and height 'h' is $2\pi rh$.

1. True
2. False

Q. An iron rod of diameter 1cm and length 8cm is drawn into a wire of length 18m of uniform thickness. Find the thickness of the wire?

Q. The diameter of the base of a right circular cylinder is 20 m and its height is 42 m. Find its curved surface area.

1. 5386 $m^2$
2. 2210 $m^2$
3. 1320 $m^2$
4. 2640 $m^2$

Q. A rectangular piece of paper of dimensions 6 cm by 22 cm is rolled along its length to form a cylinder. Find the volume of the cylinder so formed.

1. $234{\text{cm}}^3$
2. $462{\text{cm}}^3$
3. $231{\text{cm}}^3$
4. $265{\text{cm}}^3$

Q.

A cylinder has a radius of $6\mathrm{inches}$ and a height of $15\mathrm{inches}$. What is the surface area of the cylinder? Express the answer in terms of $\mathrm{\pi }$.

Q. A rectangular sheet of paper, $44cm\times 20cm$, is rolled along its length to form a cylinder. Find the volume of the cylinder so formed.

Q.

Question 45

Volume of a cylinder with radius h and height r is ___

Q. The ratio of total surface area to lateral surface area of a cylinder whose radius is 20 cm and height 60 cm is ____.

1. 2:1
2. 3:2
3. 4:3
4. 5:3

Q. Question 2
The diameter of cylinder A is 7 cm and the height is 14 cm. Diameter of cylinder B is 14 cm and height is 7 cm. Without doing any calculations can you suggest whose volume is greater? Verify it by finding the volume of both the cylinders. Check whether the cylinder with greater volume also has greater surface area.

Q. Total surface area of a cylinder with radius 'r' and height 'h' is $2\pi rh$.

1. True
2. False

Q.

Question 91

The thickness of a hollow metallic cylinder is 2 cm. It is 70 cm long with outer radius of 14 cm. Find the volume of the metal used in making the cylinder, assuming that it is open at both the ends. Also, find its weight if the metal weighs 8 g per $c{m}^3$.

Q. Choose the correct pair.


(Here LSA - Lateral surface area, CSA - Curved surface area, TSA - Total surface area)

1. $2\pi r(h+r)$
2. $4a^2$
3. $2\pi rh$
4. LSA of Cube
5. LSA of Cuboid
6. $6a^2$
7. TSA of Cube
8. TSA of Cubiod
9. TSA of Cylinder
10. $2h(l+b)$
11. $2(lb+bh+hl)$
12. CSA of Cylinder

Q. The radius of the base of a cylindrical wooden block is 5 cm and its volume is 1100 cu cm. How many discs of radius 5 cm and height 2 cm can be cut from this block of wood?

Q. The diameter of a roller is $84cm$ and its length is $120cm$. It takes $500$ complete revolutions to move once over a level a playground. Find the area of the playground in $m^2$.

1. $1584m^2$
2. $1284m^2$
3. $1554m^2$
4. none of the above

Q.

A rectangular cardboard of width 38 cm is rolled along its width and a cylinder of radius 21 cm. is formed. Find the volume of the cylinder. [2 MARKS]

Q. A cylindrical pillar is $50$ cm in diameter and $3.5$ m in height. Find the cost of painting the curved surface of the pillar at the rate of Rs $12.50/m^2$.

1. Rs. $47.50$
2. Rs. $68.75$
3. Rs. $56.12$
4. Rs. $75.12$

Q. The base diameter and height of a metallic solid cylinder are 18 cm and 24 cm respectively. If the cylinder is melted to form cylinders of base diameter 12 cm and height 6 cm, how many such small cylinders will be formed?

1. 9

Q. Find the cost of painting the outside surface of a solid cylinder of diameter $7$ m and height $25$ m at Rs.$8$ per square metre.

Q. Tick (✓) the correct answer:
The ratio of the radii of two cylinders is 2 : 3 and the ratio of their heights is 5 : 3. The ratio of their volumes will be
(a) 4 : 9
(b) 9 : 4
(c) 20 : 27
(d) 27 : 20

Q.

Raghu had to make a cylindrical aluminium tube. What is the area of the aluminium sheet required to make the tube, if the length of the tube is 1 m and the base radius is 3.5 cm? (Take $\pi =\frac{22}{7}$)

1. 2200 m²

2. 220 cm²

3. 220 m²

4. 2200 cm²

Q. A mansion has $12$ right cylindrical pillars each having radius $50cm$ and height $3.5m$. Find the cost to paint the lateral surface of the pillars at Rs.$20$ per square metre.

Q.

Eight times the sum of the areas of two circular faces of a cylinder is equal to the four times the curved surface area of the cylinder. It is given that the diameter of the cylinder is 4n, where n is an integer and height of the cylinder is 8 cm. Find the value of n.

___

Q. $10$ cylindrical pillars of building have to be painted. The diameter of each pillar is $70$ cm and the height is $4$ m. What is the cost of painting at the rate of Rs. $5$ per square metre?

1. Rs. $440$
2. Rs. $480$
3. Rs. $400$
4. Rs. $500$

Q. A square sheet, whose side is 88 cm, is rolled into a cylinder along one of its sides. What is the volume of the cylinder?
(Take $\pi =\frac{22}{7}$)

1. ${\text{94, 864 cm}}^3$
2. ${\text{54, 208 cm}}^3$
3. ${\text{27, 104 cm}}^3$
4. ${\text{13, 522 cm}}^3$