ICSE Class 9 Answered
A hydrometer of weight 10.5 gf, has the area of cross-section of its stem 0.2 cm2. If the bulb of hydrometer has a volume of 8.5 cm3, find the
1. density of liquid in which only bulb of hydrometer gets immersed
2. density of another liquid in which 1.5 cm of its stem gets immersed
Asked by Topperlearning User | 04 Jun, 2014, 01:23: PM
Expert Answer
Wt of hydrometer = 10.5 gf
Volume of liquid displaced = Volume of the bulb = 8.5 cm3
Also, by the law of flotation
Wt. of liquid displaced = Wt. of hydrometer = 10.5 gf
Therefore, Density of liquid = 
2. Volume of liquid displaced = Volume of bulb + Volume of 1.5 cm of stem
= 8.5 cm3 + 1.5 X 0.2 cm3 = 8.8 cm3
Mass of liquid displaced = Mass of hydrometer = 10.5 g
Therefore, Density of liquid = 
Answered by | 04 Jun, 2014, 03:23: PM
