... also increase to match it (up to a certain limit). Explain what would happen if the downward force (i.e. the weight) of a rowing boat in a river exceeded the reaction of the surface of the water beneath it
Answers (1)
The surface of the water has nothing to do with it. All the weight of water above a point pushes down on that point, and all the water below that point pushes up with an equal force. If anything such as a boat is pushed into the water it displaces an equal volume of water. That volume of water is forced up so the water beneath the boat pushes up with a force equal to the weight of the displaced water. If that weight is equal to the weight of the boat, the boat floats. If the force is less than the weight of the boat, the boat sinks. The surface of the water has nothing to do with it.