A flat coal seam of thickness (t) 3m is excavated and broken roof rock has completely filled the space created due to extraction as shown in the figure. If the bulking factor of roof rock is 1.2. the caving height (H) in m is<br><img src="/images/question-image/mining-engineering/introduction-to-mining-engineering/1682334963-M2-1.1-84-14.PNG" title="Introduction to Mining Engineering mcq question image" alt="Introduction to Mining Engineering mcq question image">

Correct Answer: 15