Surface Area of a Hollow Cylinder

Q.

There is a hollow cylinder as shown in figure having an inner and outer radius as 7 cm and 14 cm respectively and height is 28 cm. A man wants to paint it completely inside out. The area which he needs to paint is equal to:

1. $4640c{m}^2$
   

2. $4820c{m}^2$

3. $5260c{m}^2$

4. $4620c{m}^2$

Q.

Curved surface area of a cylinder of radius $r$ and height $h$ is _______

Q.

Your friend finds the surface area of the cylinder. Is your friend correct? Explain your reasoning

Q.

It is required to colour paint a glass cylindrical chimney of height 20 m and base diameter 14 m. Find the area to be painted.($\pi =\frac{22}{7}$)

Q.

The total surface area of a cylinder of radius 'r' and height 'h' is _____.

1. $2\pi rh+\pi r^2$
2. $2\pi r^2$
3. $2\pi rh$
4. $2\pi r(h+r)$

Q. Which among the following represents the total surface area of the right circular cylinder?

1. $2\pi r^2+\pi rh$
2. $2\pi r(r+h)$
3. $2\pi r^2(1+h)$
4. $2\pi r^2+\pi r^{2}h$

Q.

There is a hollow cylinder as shown in the figure having outer radius 7 cm, height 21 cm and inner radius 6 cm, whose inner and outer surfaces are to be painted. Calculate the area to be painted.

1. $792c{m}^2$
   

2. $924c{m}^2$
   

3. $1716c{m}^2$
   
   

4. $132c{m}^2$

Q.

Two edges of a rectangular sheet of paper having dimensions 14m $\times$ 7m are held together so that it forms a cylinder. Find the curved surface area of the cylinder.

1. 98$m^2$

2. 100$c{m}^2$

3. 88$c{m}^2$

4. 78$m^2$

Q.

The difference between the inner surface area and the outer surface area of a hollow cylinder having height 7 cm and inner and outer radius of 3 cm and 4 cm respectively is:

1. $22c{m}^2$

2. $88c{m}^2$

3. $44c{m}^2$

4. $42c{m}^2$

Q.

A rectangular paper is folded into a cylinder. The length and breadth of the paper are L and B respectively. What is the outer surface area of the cylinder?

1. $\pi$LB

2. 2$\pi$LB

3. 2LB

4. LB

Q.

If the height of the cylinder is doubled, by what number must the radius of the base be multiplied so that resulting cylinder has the same curved surface area as the original cylinder?

1. 2
2. 4
3. 0.25
4. 0.5

Q. The formula for lateral surface area of a cylinder of radius 'r' and height 'h' is

1. $\pi rl$
2. $2\pi rh$
3. $\pi r^{2}h$
4. $\pi rh$