Calculation Energy in our Bodies, Energy in our Lives

Goals: To learn about energy, how it is produced and its sources; To understand the concept of energy efficiency and explore what each of us can personally do to reduce your energy consumption.

Duration: 30 minutes

Materials: 1 – 13 Watt Compact Fluorescent Light bulb (CFL)

1 – 60 Watt Incandescent light bulb

2 Table Lamps

Cookies or other packaged food

Audience: Grades 4+

Procedure: Part 1

1) Start with a 2 minute eating meditation over a cookie (or something else packaged)

Elements to include in the eating meditation:

Say the Bracha (Blessing), most likely Boreh Mineh Mezonot

Close your eyes,

Put the cookie on the tip of your tongue, but don’t eat it, just let it sit there.

Now, chew the cookie slowly, feel the food breaking down in your mouth.

Notice the different flavours within the cookie, identify each of them

Swallow the cookie and feel it move down to your stomach

Let the food digest slightly, open your eyes, how do you feel

2) Read the ingredient information from the packaging.

3) What ingredients are giving the food its energy/calories. (Make sure students understand calories as a measure of food energy)

4) Calculate how many calories each person is getting from the food, and how many the class as a whole consumed (from the nutritional information). Convert food calories to energy that we use in our home (860 cal from food = 1 Kwh of electricity).

Part 2

5) Put the two different light bulbs in the two lamps and plug them in.

6) Turn on the two lamps and begin timing, they should be on for exactly 10 minutes.

7) While you wait, discuss how humans use food energy to live, breath, move, etc.

Activity – Do 20 jumping jacks, then feel the heat on the back of your head, discuss energy usage and loss.

8) Turn off lamps (after 10 minutes) compare the heat coming off the two lights. Incandescent – too hot to touch, CFL only slightly warm

9) Compare energy usage of the two bulbs in that period. How many cookies would it take to power each light bulb?

Incandescent – 0.01 Kwh (for 10 minutes)

Compact Fluorescent – 0.0022 kwh (for 10 minutes)

10) Read the following passage:

“Rav Zutra says ‘Whoever covers an oil lamp, or uncovers a naphtha lamp, transgresses the law of bal tashchit.” Talmud Shabbat, 67b

How does this biblical verse apply to our energy choices today

11) Read the following passage:

"Rav Hisda says, ‘one who could eat barley bread, but eats wheat bread has violated "bal tashchit.’ Rav Pappa says, ‘one who could drink wine, but drinks beer, has violated bal tashchit.” [Because they use more resources to produce]" Talmud Shabbat 140b

How does this biblical verse apply to our food choices today.

Hints: Think about the energy it takes for food to travel, be processed, packaged, etc.

Some facts about CFL’s:

Greater than 4 times more efficient and last 5 – 10 times longer than an incandescent bulb.

A 13 watt CFL gives the same amount of light as a 60 watt incandescent bulb.

They use 50-80% less energy than an incandescent.

Replacing one bulb will keep ½ ton of CO2 out of the atmosphere for the life of the bulb.

If everyone in Canada used energy efficient lighting we could shut down 10 average sized power plants.

If everyone in the USA used energy efficient lighting we could shut down over 100 average sized power plants.

Materials developed by Noam Dolgin, www.noamdolgin.com.

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