Question

The top surface of a coal seam is exposed at 150 m contour level on a hill top at location A. The same surface of the seam is also exposed on a river bed at location B at the 50 m contour level. The aerial distance A-B is 1 km. The amount of dip of the coal seam along A-B is (degree). (Give answer in one decimal place).

Hint:

Dip can be calculated using the vertical and horizontal distance between two points along the surface of a bed.

Answer 1

Correct Answer: 5

Step 1: Understanding the question.
The question asks for the dip of the coal seam based on the difference in contour levels and the horizontal distance between locations A and B.
Step 2: Analyzing the solution.
The formula to calculate the dip is given by: \[ \text{Dip} = \tan^{-1}\left(\frac{\text{Vertical Distance}}{\text{Horizontal Distance}}\right) \] The vertical distance is \(150 - 50 = 100 \, \text{m}\) and the horizontal distance is 1 km = 1000 m. Substituting into the formula: \[ \text{Dip} = \tan^{-1}\left(\frac{100}{1000}\right) = \tan^{-1}(0.1) = 5.7° \] Step 3: Conclusion.
The correct answer is 5.7°.