Surface area of combined figures

Q.

In a building there are $24$ cylindrical pillars. The radius of each pillar is $28cm$ and height is $4m$. Find the total cost of painting the curved surface area of all pillars at the rate of $8$ per $m^2$

Q.

Question 56

State whether the following statement is true or false:

​​​​​​​Two cuboids with equal volume will always have equal surface area.

Q.

A tent consists of a cylinder surmounted by a cone. Which of the following does the total surface area of the tent not consist of?

1. One circuler section of cylinder, Base area of cone

2. C.S.A of cone, C.S.A of cylinder

3. C.S.A of cone, Base area of cone

4. C.S.A of cone

Q.

There is a retangular metal plate. I make a dent on the middle of the plate with a hammer to produce a conical depression. The top side of the metal is polished. What is the area of the metal polished?

1. Area of rectangle + Area of central circle - C.S.A of cone

2. Area of rectangle + Area of central circle + C.S.A of cone

3. Area of rectangle + C.S.A of cone

4. Area of rectangle – Area of central circle + C.S.A of cone

Q.

A piece of cloth is required to completely cover a solid object. The solid object is composed of a hemisphere and a cone surmounted on it. If the common radius is 7 m and height of the cone is 1 m, what is the area of cloth required?

1. 463.39 $m^2$

2. 262.39 $m^2$

3. 662.39 $m^2$

4. 563 $m^2$

Q.

From a solid cylinder whose height is 2.4 cm and diameter 1.4 cm, a conical cavity of the same height and same diameter as that of cylinder is hollowed out. Find the total surface area of the remaining solid. $(Use\pi =\frac{22}{7})$

1. $19.60{\text{cm}}^2$

2. $15.60{\text{cm}}^2$

3. $18.60{\text{cm}}^2$

4. $17.60{\text{cm}}^2$

Q.

2 cubes each of volume 64 $c{m}^3$ are joined end to end. Find the surface area of the resulting cuboid (in $c{m}^2$)

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Q.

A tent is in the form of a cylinder of diameter 4.2 m and height 4 m, is surmounted by a cone of equal base and height 2.8 m. Find the cost of canvas required for making the tent at ₹100 per sq.m.

1. ₹ 6590

2. ₹ 7590

3. ₹ 8590

4. ₹ 9876

Q.

There is a toy rocket in the shape shown below. The base radius of the cylinder = 1.5 cm. Base radius of the cone = 2.5 cm. Find the total surface area (in sq.cm) of the toy.

1. 60π

2. 70π

3. 90π

4. 82.5π

Q.

There is a solid wooden cuboidal block of length, breadth and height 10 m, 8 m and 5 m respectively. On the top face of the block is a hemispherical depression of radius 3 m. What is the surface area of the solid so obtained?

1. 301

2. 408

3. 348

4. 368

Q.

A cubical block of side 7 cm is surmounted by a hemisphere. Find the surface area of the solid(in $c{m}^2$ ).

1. 332.5 $c{m}^2$

2. 346.8 $c{m}^2$

3. 312.5 $c{m}^2$

4. 320 $c{m}^2$

Q.

A wooden article was made by scooping out a hemisphere from each end of a solid cylinder. If the height of the cylinder is 10 cm and its base is of radius 3.5 cm, find the total surface area of the article (in $c{m}^2$).

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Q.

There is cylindrical platform on the ground. On top of this, I place a cylindrical flag pole which is hollow. I want to paint both the flag pole and the platform with blue paint. What is the area that needs to be painted?

1. C.S.A of pole + C.S.A of platform – Base area of pole

2. C.S.A of pole + C.S.A of platform

3. C.S.A of pole + C.S.A of platform + Base area of pole + Base area of platform

4. C.S.A of pole + C.S.A of platform + Base area of platform – Base area of pole

Q.

There are 2 identical cubes each having a total surface area equal to ‘A’. Let ‘S’ be the surface area of the solid obtained by joining these 2 cubes end to end. Which of the following statements is true?

1. S = 2A

2. S > 2A

3. S < 2A

4. Cannot be determined