Answer:
3.2
Explanation:
The computation of the relative density of the body is shown below:
Given that
W denotes the weight of the body in air = 160 N
ρ' denotes density of the body
V denotes volume of the body
Now weight of the body in the air is
W = ρ' V g ............................... (1)
And,
W' denotes weight of the body in liquid = 120 N
Now the force of buoyancy is
F = W - W'
= 160 - 120
= 40 N
And, ρ denotes density of liquid
The force of buoyancy is
F = ρ V g .................................(2)
Now divide equation 1 from equation 2
160 ÷ 40 = ρ' V g ÷ (ρ V g )
4 = ρ' ÷ (0.8 )
ρ' = 3.2