# Day 170: Kill-a-Watt

Advanced Physics:

Part one of the final exam– The conceptual set of questions.  I also handed out the Semester 2 Lab Practical they will complete on Tuesday.  A requirement for this part it to do a some pre-planning and answer three simple questions (Posted on Schoology) about it: (1) What is the purpose? (2) What data will you gather and with what equipment?, and (3) How will you analyze the data you gathered to solve the problem?  So far, some very interesting approaches.  It is hard for me to not give any suggestions or help.

General Physics:

Today, the students completed an activity had them calculating the cost of various appliances given some time values.  We set up six stations, each will a Kill-a-Watt meter.  These are awesome little devices that allow the students to make measurements on appliances as the appliance is being used.  Here are the stations we set up:

1.  Comparing the power for a 40-watt incandescent bulb and a 10 energy-efficient compact fluorescent equivalent and how much money over the course of a year could be saved.

2. A microwave warming some ‘coffee’ (or water in this case).

3.  Comparing a Wii gaming system and X-Box 360 (unfortunately we only had the Wii to play with).

4.  A cell phone charger … measure the power with the phone connected and not connected.

5.  A mock kitchen circuit — For this one, we monitored current.  We plugged in a light (100 watt), a toaster, and a stove (or hot plate in this case), and the students recorded how the current changed.  The questions for this station related to parallel circuits and why the current goes up… what would happen if a lamp was added …it would have tripped the circuit breaker.  For next year, I’d love to set up and actual circuit breaker so the students can see this happening.

6.  A Smartboard.  Every science room (10) in our building has a Smartboard.  The students calculated to cost of using all of them for 30 minutes a mod (7 total) for the entire year.