Question

How does the buoyant force acting on the boat change if the boat is loaded so that more of the boat is below the water?

• A. The buoyant force increases.
• B. The buoyant force decreases.
• C. The buoyant force stays the same.
• D. The buoyant force decreases, then returns to the original value.

Answer 1

The correct option is A The buoyant force increases.

Answer is A.

When a body is partly or completely immersed in water (or any other liquid), then:
Loss in weight of body = Weight of water (liquid) displaced by the body = Buoyant force or upthrust exerted by water (any liquid) on the body.
In this case, the increased displacement of water, multiplied by the weight of that water, equals the buoyancy force.
Therefore, as the boat is loaded so that more of the boat is below the water, the displacement volume increases, then the water displaced increases and hence the buoyant force increases.