1.Hard wood is strong in tension and weak in compression.
a) True
b) False
Explanation: Soft wood is strong in tension and weak in compression. Hard wood is equally strong in tension and compression.
2. Exogenous trees are further divided into:
a) 3
b) 4
c) 2
d) 5
Explanation: Exogenous trees are those in which trees grow outward. The 2 types are coniferous (evergreens) and deciduous (broad leaf) trees.
3. Which of the below is a property of soft wood?
a) Medullary rays are less distinct
b) Annual rings are less distinct
c) Dark in colour
d) Close grained structure
Explanation: The other 3 options are properties of hard wood. Soft wood is light in colour, annual rings are clearly visible and it has resinous structure.
4. The surface of freshly cut timber should be:
a) Soft and shining
b) Hard and shining
c) Perfectly round
d) Light in colour
Explanation: Dull appearance is a sign of defective timber. Soft surface is prone to attack by insects, fungus and is not a good quality.
5. The quality of timber does not depend upon:
a) Maturity of tree
b) Time of felling
c) Type of tree
d) Size of tree
Explanation: The size of a tree is not of much importance. The weight, maturity of tree matters and not length.
6. How should the smell of a freshly cut timber be?
a) Sweet
b) Pungent
c) Unpleasant
d) Odourless
Explanation: One can detect the quality of a timber by smelling freshly cut timber. Ideally, it should be sweet. Unpleasant smell indicates decay of timber.
7. Where is the property of shock resistance an important parameter?
a) Furniture
b) Utensils
c) Tool handles
d) Doors
Explanation: A good timber should be capable of resisting shocks. Tool handles, parts of motor cars, aeroplanes should use timber that has good shock resistance.
8. Timbers with ___________ annular rings are generally the strongest.
a) Narrow
b) Wide
c) Distinct
d) Indistinct
Explanation: Annular rings are formed every year and they consist of innumerable cells of fibres and tissues. Total number of annular rings indicate an age of tree. Narrow annular rings indicate the strength of tree.
9. How can the quality of timber be checked via sound?
a) Timber struck by hammer
b) Timber tapped by hand
c) Timber knocked by chisel
d) Two timber pieces struck together
Explanation: Just as in the case of bricks, two timber pieces are taken and struck against each other. A good quality timber should make a clear ringing sound.
10. How should be the colour of good quality timber?
a) Light
b) Gradient
c) Dark
d) Brown
Explanation: Heart wood consists of dead cells which are free from sap, hard, dark in colour. Hence, dark coloured wood is preferred. Light colour indicates low strength.