# Volume and surface area

##### Active member

A right triangle with sides 3 cm, 4 cm and 5 cm is rotated the side of 3 cm to form a cone. The volume of the cone so formed is:
 A. 12 cm3 B. 15 cm3 C. 16 cm3 D. 20 cm3

#### Himanshi Agarwal

##### Active member
In a shower, 5 cm of rain falls. The volume of water that falls on 1.5 hectares of ground is:

A. 75 cu. m
B. 750 cu. m
C. 7500 cu. m
D. 75000 cu. m

A hall is 15 m long and 12 m broad. If the sum of the areas of the floor and the ceiling is equal to the sum of the areas of four walls, the volume of the hall is:

A. 720
B. 900
C. 1200
D. 1800

66 cubic centimetres of silver is drawn into a wire 1 mm in diameter. The length of the wire in metres will be:

A. 84
B. 90
C. 168
D. 336

##### Active member
In a shower, 5 cm of rain falls. The volume of water that falls on 1.5 hectares of ground is:

A. 75 cu. m
B. 750 cu. m
C. 7500 cu. m
D. 75000 cu. m

A hall is 15 m long and 12 m broad. If the sum of the areas of the floor and the ceiling is equal to the sum of the areas of four walls, the volume of the hall is:

A. 720
B. 900
C. 1200
D. 1800

66 cubic centimetres of silver is drawn into a wire 1 mm in diameter. The length of the wire in metres will be:

A. 84
B. 90
C. 168
D. 336
1. B 2. C

##### Active member
A hollow iron pipe is 21 cm long and its external diameter is 8 cm. If the thickness of the pipe is 1 cm and iron weighs 8 g/cm3, then the weight of the pipe is:

A. 3.6 kg
B. 3.696 kg
C. 36 kg
D. 36.9 kg

A boat having a length 3 m and breadth 2 m is floating on a lake. The boat sinks by 1 cm when a man gets on it. The mass of the man is:

A. 12 kg
B. 60 kg
C. 72 kg
D. 96 kg
50 men took a dip in a water tank 40 m long and 20 m broad on a religious day. If the average displacement of water by a man is 4 m3, then the rise in the water level in the tank will be:

A. 20 cm
B. 25 cm
C. 35 cm
D. 50 cm

##### Active member
A hollow iron pipe is 21 cm long and its external diameter is 8 cm. If the thickness of the pipe is 1 cm and iron weighs 8 g/cm3, then the weight of the pipe is:

A. 3.6 kg
B. 3.696 kg
C. 36 kg
D. 36.9 kg

A boat having a length 3 m and breadth 2 m is floating on a lake. The boat sinks by 1 cm when a man gets on it. The mass of the man is:

A. 12 kg
B. 60 kg
C. 72 kg
D. 96 kg
50 men took a dip in a water tank 40 m long and 20 m broad on a religious day. If the average displacement of water by a man is 4 m3, then the rise in the water level in the tank will be:

A. 20 cm
B. 25 cm
C. 35 cm
D. 50 cm
1. B 2. B

##### Active member
The slant height of a right circular cone is 10 m and its height is 8 m. Find the area of its curved surface.

A. 30 m2
B. 40 m2
C. 60 m2
D. 80 m2

A cistern 6m long and 4 m wide contains water up to a depth of 1 m 25 cm. The total area of the wet surface is:

A. 49 m2
B. 50 m2
C. 53.5 m2
D. 55 m2

A metallic sheet is of rectangular shape with dimensions 48 m x 36 m. From each of its corners, a square is cut off so as to make an open box. If the length of the square is 8 m, the volume of the box (in m3) is:

A. 4830
B. 5120
C. 6420
D. 8960

##### Active member
The slant height of a right circular cone is 10 m and its height is 8 m. Find the area of its curved surface.

A. 30 m2
B. 40 m2
C. 60 m2
D. 80 m2

A cistern 6m long and 4 m wide contains water up to a depth of 1 m 25 cm. The total area of the wet surface is:

A. 49 m2
B. 50 m2
C. 53.5 m2
D. 55 m2

A metallic sheet is of rectangular shape with dimensions 48 m x 36 m. From each of its corners, a square is cut off so as to make an open box. If the length of the square is 8 m, the volume of the box (in m3) is:

A. 4830
B. 5120
C. 6420
D. 8960
1. C 2. A

##### Active member
The curved surface area of a cylindrical pillar is 264 m2 and its volume is 924 m3. Find the ratio of its diameter to its height.

A. 3 : 7
B. 7 : 3
C. 6 : 7
D. 7 : 6

A cistern of capacity 8000 litres measures externally 3.3 m by 2.6 m by 1.1 m and its walls are 5 cm thick. The thickness of the bottom is:

A. 90 cm
B. 1 dm
C. 1 m
D. 1.1 cm

What is the total surface area of a right circular cone of height 14 cm and base radius 7 cm?

A. 344.35 cm2
B. 462 cm2
C. 498.35 cm2
D. None of these

##### Active member
The curved surface area of a cylindrical pillar is 264 m2 and its volume is 924 m3. Find the ratio of its diameter to its height.

A. 3 : 7
B. 7 : 3
C. 6 : 7
D. 7 : 6

A cistern of capacity 8000 litres measures externally 3.3 m by 2.6 m by 1.1 m and its walls are 5 cm thick. The thickness of the bottom is:

A. 90 cm
B. 1 dm
C. 1 m
D. 1.1 cm

What is the total surface area of a right circular cone of height 14 cm and base radius 7 cm?

A. 344.35 cm2
B. 462 cm2
C. 498.35 cm2
D. None of these
1. B 2. B