Question

A ship of mass 1200 tons floats in sea water. What volume of sea water does it replaced? If the ship enters the fresh water, what mass of cargo must be unloaded so that the same volume of water is displaced as before? (density of fresh water=1000kg m^-3,relative density of sea water= 1.03 ; 1ton = 1000kg).

Answer 1

when the ship enters the fresh

 the volume  replaced will be  1 ton

if it enters fresh water it becomes 0.17 ton

   so the mass of cargo that should be unloaded is 0.3 ton.

Answer 2

Answer:

Volume of sea water displaced = 1.17×10³ m³

Mass that must be unloaded = 30 tonnes or 3×10⁴ kg

Explanation:

• What volume of sea water does it displace?

mass of ship = 1200 tonnes = 1.2×10⁶ kg

Mass of Ship = Mass of displaced sea water

1.2×10⁶ = 1030 (density of sea water) × Volume of sea water displaced

V = 1.2×10⁶÷1030

V = 1.17×10³m³

• What mass of cargo must be unloaded?

if equal volume of water is displaced in fresh water,

Mass of ship = Mass of equal volume of water

M = 1000(density of fresh water) × Same volume

M = 1000 × 1.17×10³

M = 1.17×10⁶kg

Therefore, mass that must be unloaded,

1.2×10⁶ - 1.17×10⁶

= 3×10⁴kg or 30 tonnes