Nov. 18 – Potential Difference and Current in Series and Parallel

Learning Goals: Understand what happens to potential difference and current in series and parallel circuits.

Success Criteria: You can solve circuits to find the missing potential difference or current.

Cells

Have a look at these diagrams:

What's the difference?  When cells are in series, you add up the potential difference.  When they're in parallel the potential difference is the same as if they were one cell.  Here's another way to think about it...

Cells in series add up, like a bunch of acrobats on top of each other.
Together, the add up and lift the electrons up very high.  V = V1 + V2 + V3 + V4 + V5.

Cells in parallel do not add up, like a bunch of acrobats standing next to each other.
Together, they all lift the electrons the same height.  V = V1 = V2 = V3 = V4 = V5.

They advantage of putting cells in parallel is that they each have to do less work.  Cells in parallel will last longer!

Loads

We then looked at loads in series and parallel.

Handouts: 

• Voltage and Current in Series and Parallel
• Voltage and Current in Series and Parallel - solutions
• Ohm's Law Worksheet 2

Please have a look at the solutions, particularly the table that describes the different situations.

You must know when to add current and when to add the potential difference (voltage).

The equations provided in the worksheet will also be provided on your equation sheet on the test.


Homework

Complete Ohm's Law Worksheet 2.

Announcement

The UNIT TEST has been moved to Nov. 27th to accommodate people who are going on the music trip.