Mirrors, Fields and Forces

Honors Physics spent time discussing color and polarization. The additive and subtractive color systems can be tricky to work with, so spend time really thinking about your answers to the homework questions. Polarization is relatively straightforward and today’s videos showed just how dramatic the effects of polarization can be. Tomorrow, we’ll review these concepts and then move on to the next chapter – refraction.

Physical Science B discussed electric charge, fields and forces. The final two methods for producing a an electric charge on a neutral object (conduction and induction) and discussed examples of each. Folks got a chance to visualize electric fields with field line diagrams and describe changes in electric potential energy based on position change of a charged particle in an electric field. Finally, the formula for Coulomb’s Law was presented and compared with that for gravitational force. Both forces are directly dependent on the magnitude of the property of matter generating the force (mass for gravity and charge for electric force) and inversely proportional to distance squared. You’ll get math practice tomorrow with Coulomb’s Law so don’t forget your calculator.

Physical Science E reviewed their static electricity experiments and began to explore the concept of static charge in more detail. The property of charge was described and related to the production of electric forces and fields. Methods of charging neutral objects was discussed and the basic properties of the three main subatomic particles (protons, neutrons and electrons) were reviewed. Tomorrow, we’ll take a more quantitative look at electric forces and fields before moving on to electric current.

Physics F and G had a final discussion of their lab activities and then turned attention back to the properties of mirrors. Plane mirrors were reviewed and the characteristics of convex and concave mirrors were introduced. The rules for drawing ray diagrams were presented and students got some practice seeing how these diagrams verified the mirror equation.

Homework

Honors Physics A: Conceptual Challenge p. 545 and Chapter Review items #37-45
Physical Science B and E: None
Physics F and G: None