Question

The figures show four different schematics of a flexible thread. If the ends are pulled apart, which of the schematic(s) will form a knot?

• A. A
• B. B
• C. C
• D. D

Hint:

When observing schematics of flexible threads, identify loops that would interlock when the ends are pulled.

Answer 1

The Correct Option is A, B

Step 1: Understanding the problem.
A knot is formed when a loop is created and the ends are pulled through, creating an interlocking pattern. The key is to observe which schematic forms a loop that would result in a knot when pulled.
Step 2: Analyzing the schematics.
- (A) shows a loop that will form a knot when the ends are pulled. - (B) also shows a loop that forms a knot. - (C) does not form a knot as the ends are not in a way that would interlock. - (D) similarly does not form a knot.
\[ \boxed{(A) \text{ and } (B) form knots.} \]