A wooden cylindrical pole is 7 m high and its base radius is 10 cm. Find its weight if the wood weighs 225 kg per cubic metre.
It is given in the question that,
Radius of the cylindrical pole (r) = 10cm = 0.1m
Height of the cylindrical pole (h) = 7m
Now,
Volume of the cylindrical wooden pole = 
= 
= 
= 0.22 cm3
Now,
We know that,
Weight of the wood = 225 kg/m3
∴ Weight of the pole = 0.22× 225
= 49.5 kg
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