Goldsmiths blow the outermost zone of a flame with a metallic blow-pipe for melting gold and silver. For which one of the following reasons do they use the outermost zone of the flame?
AIt is the hottest part providing most heat.
BThis luminous zone doesn't produce any ash.
CIt is least-hottest part protecting the design of jewelry.
DMiddle zone vaporizes gold leading to loss of metal.
Q: Goldsmiths blow the outermost zone of a flame with a metallic blow-pipe for melting gold and silver. For which one of th... | UPSC CSE Pre 2020 PYQ | UPSCGPT