Monday April 23rd, 2007 (Midterm Report Card Day)

SNC 1D
- Lesson/Note: Circuit Calculations - Determining unknown Current(s)/Voltage(s)/
Resistance(s) using given values in series and parallel circuits.

- Deriving the formulas:

SERIES CIRCUITS:
Current: IT = I1 = I2 = I3 ...
Voltage: VT = V1 + V2 + V3 ...
Resistance: RT = R1 + R2 + R3 ...

PARALLEL CIRCUITS:
Current: IT = I1 + I2 + I3 ...
Voltage: VT = V1 = V2 = V3 ...
Resistance: 1/RT = 1/R1 + 1/R2 + 1/R3 ...

Remember: You should not have to memorize these formulas (or even USE them!) to solve the questions (except the resistance formula for a parallel circuit). Solve the unknowns using your UNDERSTANDING of the concepts of current, voltage, and resistance! Talk yourself through the questions, with ideas like: "Here, the electrons split up, so if there were 200mA in total and 50mA go one way, 150mA must remain to go the other way" (this would obviously be for thinking about current in a parallel circuit).



SBI 3C
- Lesson/Note: Introduction to Plants
- Make seed scroll in a jar (begin plant growing/geotropism experiment).