Descriptive Answers for PSC Exams : Scientific and Geographical Phenomena

1. Why do we hear the sound of thunder later than we see the flash to lightining?
   Because light travels much faster than sound
2. Why does sea water boil at a temperature more than hundred degree centigrade?
   Because pressure at sea level is greater than normal
3. Why a burning candle gets extinguished when it covered by a tumbler?
   Because the supply of oxygen is cut off, the flame goes out.
4. Ice packed in sawdust doesn’t met quickly why?
   Because sawdust bing bad conductor, cut of heat ray
5. Why does a neddle sink in sea whereas an iron ship floats on it?
   Because specific gravity of needle is greater than water which it replaces, therefore, it sinks. But the weight of water displaced by ship , is greater than the weight itself. Thus , ship floats due to upward thrust of water.