An object floats in water with 58 of its volume submerged. The ratio of the density of the object to that of water is

Complete Question

 An object floats in water with 5/8 of its volume submerged. The ratio of the density of the object to that of water is:

(a) 8/5

(b) 1/2

(c) 3/8

(d) 5/8

(e) 2/1

  The correct option is  d

Explanation:

 From the question we are told that

     The ratio of the  volume of the object submerged to the total volume of the object  is  

Generally the buoyancy force acting on the object is equal to the weight of the water displaced and this is mathematically represented as

Now the mass of the water displaced is mathematically represented as

While the mass of the object is mathematically represented as

So  

   =>    

From the question that it volume of the water displace (equivalent to the volume of the object in water  ) to the volume of the total object is

So

multiply 2kg by latent heat of vap