Week 11

Arrange the chemical composition of the wood in increasing order:

• Hemicellulose < Cellulose < Lignin

• Cellulose <Lignin < Hemicellulose

• Cellulose < Hemicellulose < Lignin

• Lignin < Hemicellulose < Cellulose

Choose the correct statement related to wood from the following:

• Hardwood trees generally have broad leaves and are found in temperate regions

• Softwood trees generally have needle-like leaves and are found in tropical region

• Softwood and hardwood reference to the actual hardness of wood

• The hardwood is generally porous in nature

State true or false

The formation of carlywood and latewood depends on seasonal variation in a year.

• True

• False

Which one of the following is/are correct regarding the structural features of tree stems?

• Sapwood is denser and transports the sap and moisture from the roots

• Inner bark transports sap from leaves to the growing part of the trees

• Cambium is a very thick layer between bark and wood

• Heartwood is lighter in color and provides structural support

Select the appropriate options regarding the structural properties of wood.

• Knots are good in compression

• Knot joints trunk, and branches of trees

• The compressive strength of wood is greater than the tensile strength

• Tensile strength is higher along the grains compared to perpendicular to the grains

Match the following wood components with their features:

• A-ii, B-iii, C-i

• A-i, B-ii, C-iii

• A-i, B-iii, C-ii

• A-ii, B-i, C-iii

Arrange the following directions in the decreasing order of magnitude for shrinkage in wood:

• Longitudinal Radial Tangential

• Radial Tangential Longitudinal

• Tangential Radial Longitudinal

• Longitudinal Tangential Radial

The figure below shows the wood compression failure mode when the load is applied along the grain direction. Select the correct options.

• a) Crushing by Shearing c) Wedge splitting d) Splitting e) Shearing and splitting

• a) Crushing b) Wedge splitting c) Shearing d) Splitting e) Crushing and splitting

• a) Wedge splitting b) Shearing c) Crushing d) Splitting e) Crushing and splitting

• a) Wedge splitting b) Splitting c) Crushing

  d) Shearing e) Shearing and splitting

The property of wood by which it exhibits different mechanical properties in different directions is known as ________(10 letters)

• Anisotropy

• Anisotropy

State true or false: In tension perpendicular to the grains, failure happens in latewood

• True

• False