1.) The radius of a sphere is 2r, then its volume will be
(A)4πr3/3
(B)4πr3
(C) 8πr3/3
(D) 32πr3/3
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.) A cone is 8.4 cm high and the radius of its base is 2.1 cm. It is melted and recast into a sphere. The radius of the sphere is :
(A) 4.2 cm
(B) 2.1 cm
(C) 2.4 cm
(D) 1.6 cm
4.) In a cylinder, radius is doubled and height is halved, curved surface area will be
(A) halved
(B) doubled
(C) same
(D) four times
5.) The total surface area of a cone whose radius is r/2 and slant height 2l is
(A) 2πr(l+r)
(B) πr(l+r/4)
(C) πr(l+r)
(D) 2πrl
6.) 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
7.) The lateral surface area of a cube is 256 m2 . The volume of the cube is
(A) 512 m3
(B) 64 m3
(C) 216 m3
(D) 256 m3
8.) The number of planks of dimensions (4 m × 50 cm × 20 cm) that can be stored in a pit which is 16 m long, 12m wide and 4 m deep is
(A) 1900
(B) 1920
(C) 1800
(D) 1840
9.) The length of the longest pole that can be put in a room of dimensions (10 m × 10 m × 5m) is
(A) 15 m
(B) 16 m
(C) 10 m
(D) 12 m
10.) The radius of a hemispherical balloon increases from 6 cm to 12 cm as air is being pumped into it. The ratios of the surface areas of the balloon in the two cases is
(A) 1 : 4
(B) 1 : 3
(C) 2 : 3
(D) 2 : 1
11.) In a cylinder, if radius is halved and height is doubled, the volume will be
(A) same
(B) doubled
(C) halved
(D) four times
1) D 2) C 3) B 4) C 5) B 6) B 7) A 8) B 9) A 10) A 11) C