Broken column
Question: Why does smoke from a cigarette rise in a smooth, vertical column
before it suddenly seems to scatter in a multitude of directions?
Answer: Smoke rises from a cigarette because it is hot and lighter than air.
The stream is smooth and shaped like a column because it is laminar, and all the
smoke particles travel in parallel.
The flow is laminar because the cigarette’s burning area is small, and the
energy output that is driving the stream upward is only about one watt. Larger
sources of smoke such as smokestacks or bonfires clearly do not produce…
