The soil component with particles passing through 4.75 mm IS sieve but retained on 75 micron IS sieve, is known as:
- Acobble
- BsandCorrect
- Cresidue
- Dmud
Solution
Concept
As per IS classification, sand is the soil fraction between 4.75 mm and 75 micron.
Step-by-step solution
1. Recall the IS particle size limits. 2. Gravel: 80 mm to 4.75 mm. 3. Sand: 4.75 mm to 0.075 mm (75 micron). 4. Silt and clay (fines): below 75 micron. 5. Particles that pass 4.75 mm and are retained on 75 micron are sand.
Explanation
IS 1498 divides soil by particle size. Particles that pass the 4.75 mm sieve but stay on the 75 micron sieve are called sand. Particles smaller than 75 micron are silt and clay.
Why the other options are wrong
A: Cobbles are large particles, 80 mm to 300 mm. C: Residue is not a standard IS soil size fraction. D: Mud is a common word for wet fine soil, not an IS size range.
Shortcut
Remember the sand limits: 4.75 mm to 75 μ.
Common mistake
Mixing up the sand limit (4.75 mm) with the gravel limit (80 mm).
Correct answer: B) sand