Physics 2000 JAMB Past Questions - Question 4: When a ship sails from salt water into fresh water, the fraction of its volume above the water surface will

Correct Answer

C

Explanation

When a ship sails from saltwater (which is denser than freshwater) into freshwater, the fraction of its volume above the water surface will increase. This is due to the difference in buoyancy between saltwater and freshwater.
When a ship sails from salt water into fresh water, the fraction of its volume above the water surface will decrease.

This is because fresh water is less dense than salt water. The ship displaces a certain volume of water equal to its weight. In salt water, which is denser, the ship will displace a smaller volume of water compared to fresh water. As a result, when the ship moves from salt water to fresh water, the buoyant force acting on the ship decreases. This causes the ship to sink slightly deeper into the water, reducing the fraction of its volume above the water surface.
In saltwater, the ship experiences more buoyant force, which means that it displaces less water to support its weight. When it moves into freshwater, which is less dense than saltwater, the buoyant force decreases, and the ship will displace more water to support its weight. As a result, more of the ship's volume will be above the water surface in freshwater compared to saltwater. This can be observed as the ship riding higher in the water when it transitions from saltwater to freshwater.