Class IX Surface area and volume

                                                  Class --IX 

                                                  Math

                                                  Surface Area and Volume 

                                       MULTIPLE CHOICE QUESTIONS

1.The radius of a sphere is 2r, then its volume will be

(a) 4/3π r3         (b) 4π r3       (c)8πr3/3          (d) 32 /3 πr3

2.The total surface area of a cube is 96 cm2. The volume of the cube is:

(a) 8 cm3      (b) 512 cm3        (c) 64 cm3         (d) 27 cm3

3.In a cylinder, radius is doubled and height is halved, curved surface area will be

   (a) halved       (b) doubled       (c) samev   (d) four times.

4.The total surface area of a cone whose radius is r/2 and slant height 2/ is

(a) 2πr(l+r)        (b) πr(l+r/4)       (c)π r(l+r)     (d) 2πr

5.The radii of two cylinders are in the ratio of 2 : 3 and their heights are in the ratio of 5 : 3. The ratio

of their volumes is

(a) 10:17    (b) 20:27    (c) 17:27      (d) 20:37

6.The number of planks of dimensions (4.0 m x 5.0 m x 2.0 m) that can be stored in a pit which is

40 m long, 12 m wide and 160 m deep is

(a) 1900        (b) 1920      (c) 1800       (d) 1840

7.If volume of a cube is 216 cm2 then its edge is

(a) 36 cm    (b) 6 cm       (c) 12 cm        (d) 16 cm

8.Diagonal of a cube is √6 cm. Then its lateral surface area is

(a) 6√6 cm2        (b) 36 cm2    (c) 12 cm2            (d) 8 cm2

9.A gift pack is in cuboidal shape of dimension 1.5 m, 0.75 m, 0.5 m. Tanya didn't like the paper

wrapped on the gift pack, so she removed it and wrapped the gift with a paper of her choice but left

the base, which the says will fill with her same. The difference of area of wrapping papers used is

(ignore the extra paper used to mould the corners).

(a) 1.125 cm2              (b) 0.375 cm2      (c) 0.75 m2           (d) 2.75 m2

10. Charvi has rectangular sheet of paper and wants to fold it in such a manner that the cylinder thus

formed should have maximum curved surface area. Then she should fold it.

(a) along length         (b) along breadth   (c) along any of the sides length or breadt

(d) None of these

11.A cylinder of base radius 'r' and height 'h' is dipped vertically to half the height, in a bucket full of

purple paint. Then the area of the surface which gets painted is

(a)1/2 πr2h      (b) 1/3π r2 h        (c) 4π rh        (d)π  r(h+r)

12.In a Gym, in one exercise you have to continuously toss solid cylinder jumbles and catch them.

Cylindrical jumbles are of length 1 m and base diameter also 1 m. Density of the wood used to 4 kg

per m3, then the weight tossed is

(a) 3.14 kg       (b) π /2  kg       (c) 4r kg       (d) 12.56 kg

13.  For Diwali celebrations a packet of "Anars" is bought. In that there are 5 conical Anars, with red

glittering paper wrapped on it. Jaya took a scale and noted the following informations.

Radius of the base 7 cm and slant height 10 cm. Then the total paper used to decorate the "Anars"

in the box is

(a) 220 cm2                                   (b) 1540 cm2

(c) 374 cm2                                   (d) 1870 cm2