Answer:
Step-by-step explanation:
Assume the sphere has a volume of 1 m³ and the water is fresh.
It displaces 1 m³ of water with mass of 1000 kg
If m is the mass of the sphere, then balancing forces on the sphere gives us
downward forces of
mg + mg/3
and upward buoyancy force of 1000g N which is the weight of the water displaced.
(4/3)mg = 1000g
(4/3)m = 1000
m = 750 kg
ρ = 750 kg/m³