Question

You take an empty glass jar and push it into a tank of water with the open mouth of the jar downward, so that the air inside the jar is trapped and cannot get out. If you push the jar deeper into the water, does the buoyant force on the jar stay the same? If not, does it increase or decrease? Explain.

Short answer

Answer

Buoyant force acting on jar will decrease.

Step-by-step solution

Step-by-Step Solution Step 1: Concept of buoyant force

Depending on the depth of the tank, the buoyant force of the water lifts the object.

This force acts in the upward direction and depends on the liquid density, and displacement of volume.

Explanation of the force acting on the jar inside water tank

As a result of the open mouth of the glass jar, the trapped gas inside the water tank will not be released, thus increasing its hydrostatic pressure volume.

In proportion to the depth of the jar, the pressure on the jar at the bottom is more significant than when it is at its greatest. As the jar goes down into the tank, the amount of air inside it decreases, causing a decrease in buoyancy.

Thus, the buoyant force acting on the jar will decrease.