Monday, November 22, 2010
Mon-Day 2
Physics - we reviewed circular motion and redefined/revised our view of centripetal force as a REQUIRED FORCE, that is the force that is NEEDED in order to maintain an object's circular orbit.
Recall, sometimes that force is supplied by the tension in a rope attached to the object, sometimes it is the force of friction on the tires of a car travelling in a circle, sometimes it is the object's own weight, the force of gravity on an object.
When the centripetal force requirement is NOT MET, i.e. the object is going too fast so there is not enough force capable of meeting this enormous centripetal force requirement (due to the high speed, Fc= mv^2/r is excessively high), the object will fly off tangent to the path of the circle.
We then did a few circular motion problems, using an algebraic substitution method as well as the usual plugging-in numbers method.
We then did another momentum problem.
Tomorrow, we will finish up the springs lab, as well as some Hooke's Law spring questions, and do as much of the rest of the packet before vacation.
There will be a unit test on the second and third days back from Thanksgiving vacation.
I posted the brief vacation assignment on Blackboard: it is four questions from the unit packet covering a variety of question types from this unit.
Recall, sometimes that force is supplied by the tension in a rope attached to the object, sometimes it is the force of friction on the tires of a car travelling in a circle, sometimes it is the object's own weight, the force of gravity on an object.
When the centripetal force requirement is NOT MET, i.e. the object is going too fast so there is not enough force capable of meeting this enormous centripetal force requirement (due to the high speed, Fc= mv^2/r is excessively high), the object will fly off tangent to the path of the circle.
We then did a few circular motion problems, using an algebraic substitution method as well as the usual plugging-in numbers method.
We then did another momentum problem.
Tomorrow, we will finish up the springs lab, as well as some Hooke's Law spring questions, and do as much of the rest of the packet before vacation.
There will be a unit test on the second and third days back from Thanksgiving vacation.
I posted the brief vacation assignment on Blackboard: it is four questions from the unit packet covering a variety of question types from this unit.
AP Chem - we determined the relative sizes of various particles of an isoelectronic series by determining and explaining the three factors that cause all of the trends in chemistry: Zeff, number of OPEL's, and the degree of electron electron repulsion in the valence or outermost shell.
We then discussed the trends in atomic radius, first ionization energy, and electronegativity.
We then used the quantum mechanical model of the atom to explain the anomalies in the first ionization energy trend that occurs for elements in group 3A (due to s electrons shielding of the p electron) and in group 6A (due to increase electron electron repulsion in a given valence shell p orbital).# posted by C @ 1:48 PM 
