Why wood is a unique raw material ? Give its limitations

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anatomy

#1

Wood is a unique and important raw material because of the following reasons :
(a) Wood can be transported to long distances through
rivers without much expenditure. Being light in weight, its transport charges are low.
(b) It is a poor conductor of heat.
© Dry wood does not allow passage of electricity. However, wet wood does conduct the same.
(d) Wooden buildings are warm in winter. They are cool in summer.
(e) Wood is very easy to work with even by an untrained person. Many household articles, simple tools and implements are prepared from wood even by ordinary people.
(f) Wood is able to absorb vibrations and shocks. It is, therefore, used in railway sleepers.
(g) Because of its porous nature, wood can hold paint, lacquer, varnish and other types of polishing materials.
(h) Wooden articles maintain their shape indefinitely.
(i) In can tolerate compression, pull, bending and tearing.
(j) It does not develop rusty spots or show signs of crystallisation. Treatment with special chemicals can increase its durability.
Limitations of Wood:
(a) Wood catches fire when heated to 275°C. It is, therefore, combustible.
(b) There is a lot of wastage when wood is used for developing timber articles.
© Physical and mechanical properties of wood cannot be improved to any appreciable extent. .
(d) It is liable to be attacked by termites and micro-organisms of decay.
(e) Wood swells up on becoming wet.