Vicat apparatus — standard plunger dimensions used for consistency test In the Vicat apparatus used for standard consistency of cement paste, the plunger has a diameter of 10 mm. What is its standard length (approximate)?

Introduction / Context:
The Vicat apparatus determines standard consistency and setting times of cement paste. Correct indenter dimensions are essential for comparable penetration results across laboratories and field labs.

Given Data / Assumptions:

• Cement testing per common standards (e.g., IS/ASTM), using standard Vicat equipment.
• Plunger used for standard consistency determination.
• Plunger diameter is 10 mm as given.

Concept / Approach:

Standard Vicat plungers are specified as 10 mm in diameter and about 50 mm in length to provide adequate mass and geometry for consistent penetration readings. Other needles (e.g., initial setting needle 1 mm diameter) have different sizes, but the consistency plunger is the larger 10 mm by ~50 mm component.

Step-by-Step Solution:

Verification / Alternative check:

Equipment catalogues and code appendices list the Vicat plunger as 10 mm diameter, 50 mm long for consistency testing.

Why Other Options Are Wrong:

• 30–40 mm are shorter than standard; 60 mm exceeds typical specification.
• 20 mm is too small and nonstandard for the Vicat plunger.

Common Pitfalls:

• Confusing the plunger with the 1 mm needle used for setting-time determinations.

Final Answer:

50 mm (approximately).