Question

An object weighing 2.7n while in air and 1.2n when completely immersed in water.find the relative density of the object

Answer 1

Answer:

1.8 = relative density (there are no units for relative density)

Explanation:

It displaces water equal to it's volume and gets buoyancy equal to that amount of water

2.7 - 1.2  = 1.5  N  of buoyancy

density of water = 1 gm /cc

 1.5 N = m (9.81)

    m of water displaced = .1529 kg

             152.9 cc of water will produce this buoyancy....this is the volume of the object

   

find mass of object     2.7 = m (9.81)     shows m = .2752 kg = 272.5 gm

density = mass/ volume = 272.5 / 152.9 = 1.8 gm / cc

Relative to water (which is 1 gm / cc) the relative density is 1.8

  ====> it is 1.8 times denser than water and will sink when in water....