Dip your finger into the glass of water without touching the bottom of the glass. Check if this will change the force

Dip your finger into the glass of water without touching the bottom of the glass. Check if this will change the force of water pressure on the bottom. If it changes, how? Consider two cases: a) the glass is not full of water; b) the glass is filled to the top with water.

The force F of water pressure on the bottom is calculated by the formula F = p ∙ S, where S is the area of ​​the bottom of the glass and p = ρ ∙ g ∙ h is the water pressure at the bottom, which depends on the density of water – ρ, the acceleration of gravity at the Earth’s surface – g and the height of the liquid column in the glass – h. By dipping our finger into a glass of water, without touching the bottom of the glass, we push out part of the water with our hand. If: a) the glass is not filled to the top with water, the water level will rise: the height of the liquid column in the glass will increase – h, and the pressure, and hence the pressure force, will increase to the bottom. If b) the glass is filled to the top with water, then the lowered finger will displace part of the water from the glass, while the height of the liquid column in the glass – h will not change, which means that the pressure and pressure force on the bottom will also remain the same.