Question

Angle formed by pouring flour as a heap on a flat surface is known as:

• A. \(\text{Contact angle}\)
• B. \(\text{Angle of repose}\)
• C. \(\text{Angle of rip}\)
• D. \(\text{Critical angle}\)

Hint:

The angle of repose depends on particle size, shape, and cohesion. It determines how materials like sand or flour pile up.

Answer 1

The Correct Option is B

Step 1: Understanding the angle of repose.
- The angle of repose is the maximum angle at which granular material can rest before sliding.

Step 2: Explanation of incorrect options.
- (A) Contact angle: Related to liquid adhesion, not granular flow.
- (C) Angle of rip: No such technical term in this context.
- (D) Critical angle: A general term, but not specific to granular material.
Step 3: Selecting the correct option. Since the natural piling angle of granular materials is called the angle of repose, the correct answer is (B) Angle of repose.