Have You Ever Seen the Rain?

Great song by CCR... and appropriate for today's drizzly weather...

Physics A reviewed their circular motion and gravitation tests and then their homework for buoyant forces and density. Attention then turned towards the area of pressure. Remember that pressure is as much influenced by force as it is area, so a tremendous force may correspond to a small pressure if the area is also large. We then talked about Pascal's principle and how it applied to the area of hydraulics. In a closed container of fluid, a pressure change is experienced everywhere in all directions of a fluid. This can, with the proper equipment, be used to design a machine to give us mechanical advantage. We looked at an example problem involving a hydraulic device and you have another with your homework. Tomorrow - how pressure varies with depth in a fluid column.

Physics B worked on a lab targeting buoyant forces. A mass was incrementally submerged and it was clear that with more submerged mass, the greater the volume of displaced fluid and the greater the weight of that displaced fluid. Since weight of displaced fluid equals buoyant force (Archimedes principle), the more the mass was submerged the greater the buoyant force to which it was exposed. When the mass was fully submerged, there was no further change in buoyant force, since there was no say to increased the volume or weight of the displaced fluid. We then added salt to the water and saw that, as expected, the greater density of fluid provided a greater buoyant force. We'll go over the lab tomorrow before taking on the idea of pressure.

Intro Physics discussed their two in-class questions from yesterday and then turned attention to energy. We defined energy as the ability to do work and then contrasted energy doing work (kinetic energy) with energy waiting to do work (potential energy). We further categorized energy into mechanical and non-mechanical and discussed examples of each. Lastly, we looked at the work-energy connection. A change of energy implies work done on or by an object and work done on or by an object will produce a change in the object's energy. Tomorrow, we start to look at specific energy types starting with gravitational potential energy.

Honors Physics reviewed their latent heat homework problems before reviewing for their Chapter 10 exam which is Thursday. Tomorrow, folks will get to do a quick activity for Newton's Law of Cooling and may use the downtime during the data collection to further prepare for Thursday's test.