passwella.
Menu

JAMB Physics 1978 Question 8

Question 8

Pressure

Mercury is a better barometric fluid than water because I. It needs no colouring II. Its density is many times greater than that of water III. It does not wet glass IV. It has a high vapour pressure V. It has a high boiling point. Which of the above statements are true?

  1. A.I and II only
  2. B.I, II and III only
  3. C.III and IV only
  4. D.IV and V only
  5. E.III, IV and V only.
Show the answer and explanation

Answer: B (I, II and III only)

Explanation

Mercury is shiny and easy to see, it is about 13.6 times denser than water (so the column is short) and it does not wet glass. Its vapour pressure is low, not high, so IV is false; I, II and III are the reasons.