Knots in wood reduce its strength by
- ADecreasing its density
- BInterrupting the continuity of fibersCorrect
- CAltering its moisture content
- DIncreasing its elasticity
Solution
Concept
Effect of knots
Step-by-step solution
1. Knots break the continuity of grain. 2. Local strength falls.
Explanation
Knots interrupt fibres, so they weaken timber.
Why the other options are wrong
They do not increase elasticity.
Shortcut
Knot = broken fibres.
Correct answer: B) Interrupting the continuity of fibers