Correct Answer - Option 3 : Shrinkage limit method

__Concepts:__

**The shrinkage Limit Method **is used to determine the specific gravity of solid particles. Based on Shrinkage Ratio (SR) and Shrinkage Limit (SL), the specific gravity of soil solids can be calculated using the following formula:

\(G = \frac{1}{\frac{1}{SR}-\frac{SL}{100}} \)

__Important Points:__

**1. **Oven dry method, Calcium Carbide Method, Alcohol Methods, Sand Bath Method, Torsion balance Methods are used to determine the water content of soil.

**2. **The other methods for determining the specific gravity of solid particles are – Core Cutter Method, Sand Replacement Method, Water displacement Method. These methods give the unit weight of soil, by dividing it with the unit weight of water, we can get specific gravity.

3. Pycnometer is used for determining the specific gravity of soil if we know the water content and also used for determining the water content if we know the specific gravity of soil.