1. The surface area of a sphere of radius ‘r’ is
(A) 4 π r²
(B) 2 4 π r
(C) 2 π r
(D) 4/3 π r³
2. The volume of a sphere of diameter D is
(A) 4/3 π D³
(B) 2 4 π D
(C) π D³ /6
(D) 2 π D⁴
3. If R and r are the external and internal radii of spherical shell respectively, then its volume is
(A) 2/4 π (R³ - r³)
(B) 4/3 π (R³ - r³)
(C) 4/3 π (R - r)
(D) π (R³ - r³)
4. If a plane cuts a sphere into two unequal portions then each portion is called
(A) circle
(B) segment
(C) hemi-sphere
(D) diameter
5. If two parallel planes cut the sphere by separating two segments, the portion between the planes is called
(A) surface
(B) volume
(C) zone
(D) hemisphere
6. Volume of hemi-sphere is
(A) 2/3 π r
(B) 1/2 4/3 π r³
(C) 1/3 π r²
(D) 2/3 π r³
7. Area of cloth to cover tennis ball of radius 3.5 cm is
(A) 231 sq. cm
(B) 77 sq. cm
(C) 308 sq. cm
(D) 154 sq. cm
8. Volume of sphere of radius 3 cm is
(A) 108π cu. cm
(B) 45π cu. cm
(C) 12π cu. cm
(D) 36π cu. cm