Properties of Matter 4 Question 4

6. An open glass tube is immersed in mercury in such a way that a length of 8cm extends above the mercury level. The open end of the tube is then closed and sealed and the tube is raised vertically up by additional 46cm. What will be length of the air column above mercury in the tube now? (Atmospheric pressure =76cm of Hg )

(2014 Main)

(a) 16cm

(b) 22cm

(c) 38cm

(d) 6cm

Show Answer

Answer:

Correct Answer: 6. (b)

Solution:

  1. Decrease in surface energy = heat required in vaporisation.

S=4πr2dS=2(4πr)drT(dS)=L(dm)T(2)(4πr)dr=L(4πr2dr)ρr=2TρL



जेईई के लिए मॉक टेस्ट

एनसीईआरटी अध्याय वीडियो समाधान

दोहरा फलक