How is the weight of water in a test specimen calculated?

The weight of water in a test specimen is correctly calculated by subtracting the dry weight from the wet weight. This method accurately determines the amount of water absorbed by the specimen, which is essential for understanding the material's permeability and overall performance characteristics.

When a specimen is weighed dry, it represents the weight of the material without any moisture. Once the specimen is saturated with water and weighed again (wet weight), the difference between these two measurements precisely reflects the weight of the water absorbed. This calculation is critical in various material testing processes, especially for concrete or similar substances where moisture content can significantly impact strength, durability, and stability.

Other methods like weighing the water individually or adding weights do not directly address the measurement of absorbed water in a specimen, making them unsuitable for this particular calculation.