Class IX Math
Hots for Surface Areas and Volumes
1. A brick measures 30 cm × 10 cm ×
How many bricks will be required for a wall 30 m long. 2 m high and
thick?
2. The surface area of a cube is
Find its volume.
3. A hemispherical tank is emptied by a pipe at the rate of 5 litres per minute. How long will it take to half empty the tank if it is
metre in diameter:
4. If the heights of two cylinders are in the ratio of 4 : 3 and their radii are in the ratio of 3 : 4 then what is the ratio of their volumes?
5. If the radius of the base of a solid cone is 'r' and its slant height is 1 then what is its lateral surface area?
6. What is the total surface area of a cone, whose radius
and slant height = 31?
7. If a right circular cone has radius 4 cm and slant height 5 cm then what is its volume?
8. The radius of a hemisphere is r. What is its volume?
9. If the radius of a sphere is 2 r, then what is its volume?
10. If the radius of a sphere is doubled then what is the ratio of their volumes?