Which of the following is the measure of ease with which the wood may split?
Try it first: pick an option, then read the explanation.
Mechanical Properties of Timber
Timber possesses various mechanical properties that determine its suitability for different applications. These properties describe how wood reacts to different types of forces. The question asks for the specific property related to splitting.
Detailed Analysis of the Options
(b) Shearing strength
This is the wood's ability to resist forces that try to slide one part of it past another. It's a measure of resistance to being "cut" or sheared, not split apart.
(c) Stiffness
Stiffness, measured by the Modulus of Elasticity, is the wood's ability to resist bending or deformation under a load. A stiff piece of wood will not bend easily. This is unrelated to splitting.
(d) Toughness
Toughness is the wood's ability to absorb shock or impact energy without breaking. A tough wood can withstand sudden blows, which is why it's used for things like tool handles and sports equipment. It is a measure of impact resistance, not ease of splitting.
(a) Cleavability
This is the correct answer. Cleavability is the specific term for the ease with which wood can be split apart along the grain. Wood splits easily along its fibres (high cleavability) but is very difficult to split across the grain. This property is particularly important when considering how wood will be worked (e.g., for firewood) or how it will perform under stresses that might cause splitting, such as when nails are driven near its edge.
Key Mechanical Properties of Wood
| Property | Description | Measures Resistance To... |
|---|---|---|
| Cleavability | Ease of splitting along the grain | Splitting / Cleaving |
| Shearing Strength | Forces sliding past each other | Shearing |
| Stiffness | Deformation under load | Bending |
| Toughness | Ability to absorb sudden energy | Impact / Shock |
Study Tips
- Cleave = Split: The word "cleave" literally means to split or sever something, especially along a natural line or grain. This makes the connection to cleavability direct.
- Think of an Axe: When you split firewood with an axe, you are testing its cleavability.
- Distinguish from Other Strengths: Be clear about the different types of strength. Stiffness is for bending, toughness is for impact, and shearing is for sliding forces. Cleavability is specifically for splitting.