Questions:
1. In 1847, a scientist discovered a temperature -- of around 525 degree C -- at which all solid objects start to glow a dim red colour. What is this point called?
2. The ________ ___________ is the temperature at which a substance spontaneously catches fire without the need for a spark or a flame. For example, this temperature for diesel is 210 degrees C and 585 degrees C for hydrogen. Fill in the blanks.
3. At a temperature of around 3.6 trillion K, objects double in mass. This is as a result of the _______ ______ of __________, which -- among other things -- relates matter’s velocity with its mass. Fill in the blanks.
4. Stars, including the Sun, fuse lighter elements before heavier ones. But one exception to this is that neon fusion happens before ______ fusion. Fill in the blank with the name of the element whose nuclei are harder to fuse because they’re more stable, and need a temperature of at least around 1.5 billion K.
5. A particle made of two or more subatomic particles is called a hadron. The ________ ___________ is the name of the temperature beyond which hadron matter can’t exist. I.e. it’s the temperature above which hadronic matter boils. Fill in the blank.
Visual:
This is the star WR 124. What does WR mean? It’s a label given to stars that, among other features, have the hottest surface temperatures, up to 210,000 K.
Answers:
1. Draper point
2. Kindling temperature
3. Special theory of relativity
4. Oxygen
5. Hagedorn temperature
Visual: Wolf-Rayet
