Burning Fragment Crossword Clue
Burning fragment crossword clue. 5 letters. A quick one crossword in The Courier-Mail newspaper on Friday 1 September 2017.
The solver: EMBER
Example of burning fragment
When your flint first strikes the steel in a vacuum you will get a spark because the heat generated from friction is concentrated and focused on one small spot (the point of contact where the tiny steel fragment is heated until glowing an broken off), and there is no gas or other medium present to conduct or convect the heat away; in fact the vacuum could potentially boost the spark longevity by somewhat inhibiting its rate of cooling.
Once a spark is struck in a normal atmosphere the friction- heated fragment of metal that is sheared off reacts with the oxygen present and burns (something which it is not able to do a lower ambient temperatures) for a short time afterwards. When this hot burning fragment contacts a fuel source, such as steel wool in the example, it sets it alight.