Question

Which of the following properties of the glass plays a key role in the Beckline method?

• A. Melting point
• B. Type of fracture
• C. Refractive Index
• D. It's manufacturing

Hint:

The Becke line method is all about matching the \textbf{refractive index} of a glass fragment to that of a series of calibrated liquids. When the "halo" (Becke line) disappears, you've found the match.

Answer 1

The Correct Option is C

Step 1: Understand the Becke Line Method. The Becke line test is an immersion method used in optical mineralogy and forensic glass analysis. It is used to determine the relative refractive index of a transparent solid (like a glass fragment) compared to a liquid it is immersed in.

Step 2: Describe the process. A glass fragment is placed in a calibrated liquid of a known refractive index. When viewed under a microscope, a halo of light, known as the "Becke line," appears around the fragment. By adjusting the focus, the line will move into the medium with the higher refractive index. The liquid is changed until the Becke line disappears, indicating that the refractive index of the glass and the liquid are the same.

Step 3: Conclude. The entire method is based on observing the behavior of light as it passes through the boundary of two substances with different refractive indices. Therefore, the Refractive Index is the key property.