*CUBOID*Let length =

*l*, breadth =*b*and height =*h*units. Then*Volume*= (*l*x*b*x*h*) cubic units.*Surface area*= 2(*lb*+*bh*+*lh*) sq. units.*Diagonal*=*l*^{2}+*b*^{2}+*h*^{2}units.

*CUBE*Let each edge of a cube be of length

*a*. Then,*Volume*=*a*^{3}cubic units.*Surface area*= 6*a*^{2}sq. units.*Diagonal*= 3*a*units.

*CYLINDER*Let radius of base =

*r*and Height (or length) =*h*. Then,*Volume*= (*r*^{2}*h*) cubic units.*Curved surface area =*(2*rh*) sq. units.*Total surface area*= 2*r*(*h*+*r*) sq. units.

*CONE*Let radius of base =

*r*and Height =*h*. Then,*Slant height,**l*=*h*^{2}+*r*^{2}units.*Volume*=*r*^{2}*h*cubic units.*Curved surface area*= (*rl*) sq. units.*Total surface area*= (*rl*+*r*^{2}) sq. units.

*SPHERE*Let the radius of the sphere be

*r*. Then,*Volume*=*r*^{3}cubic units.*Surface area*= (4*r*^{2}) sq. units.

*HEMISPHERE*Let the radius of a hemisphere be

*r*. Then,*Volume*=*r*^{3}cubic units.*Curved surface area*= (2*r*^{2}) sq. units.*Total surface area*= (3*r*^{2}) sq. units.Note: 1 litre = 1000 cm^{3}.

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 Answer: Option B

Explanation:

1 hectare = 10,000 m

^{2}So, Area = (1.5 x 10000) m

^{2}= 15000 m^{2}.Depth = 5 m = 1 m. 100 20 Volume = (Area x Depth) = 15000 x 1 m ^{3}= 750 m ^{3}.20 #### 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:

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

Correct! Wrong!#### 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:

Correct! Wrong!#### 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:

Correct! Wrong!#### 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:

Correct! Wrong!QUIZ ON VOLUME & SURFACE AREASGREAT JOB!!!!!Share your Results: