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DAY TWO - DAYTIME RADIO CHALLENGE

This day begins with the students calculating the distances to the radio stations they found as part of the AM Radio Challenge and having them report their results.

Students are then asked to try and tune their radios to the stations they found.

The groundwork for is laid for the rest of the lesson when the students are presented with the question: Why is AM reception different during the day than during the night?

Prep Work:

  1. Obtain necessary materials.
  2. Test AM reception in classroom.  It may be necessary to place radios by window or go outside.

Materials Required:

  1. Your Radio
  2. Regional maps
  3. Rulers or scales for use with maps
  4. Calculators (for scale conversions)

Class Outline:

Class should begin with the class making a list on the board of the farthest stations.   Listing should probably be limited to out-of-state stations.  (Hopefully, you'll get a lot of these!)

Students, with the use of maps, should determine the distances to the radio stations they found.

Now that students have found all of these stations at night, have them come up to the front of the classroom one at a time (maybe starting with the student who found the farthest station) and get in the furthest station they could at night.   They should have some difficulty.  Ask why.  Answers might include:  we're inside, it's daytime, your radio isn't as good.

Offer to take the class outside to try.  Remind them that, by doing so, you are removing an uncontrolled variable (inside vs. outside.)  You may want to explain how pipes, electrical conduits, and suspended ceilings are all known to interfere with radio reception.

(It is up to the teacher whether or not you first want to try this in the classroom or if you want to initially go outside, to be away from suspended ceilings and fluorescent light.)

After several students try, and fail, to get in their farthest stations, have all students INDIVIDUALLY write in their journal why they think stations that came in at home (and at night) don't come in at school (and in the daytime.)  It may be interesting to NOT emphasize the day-night dependence at this early time.  After giving the students a few minutes to write information in their logs, take time to write ideas on the board and discuss different hypotheses with the class.

At the conclusion of this exercise, you can pose one of the key questions of this lesson:

WHY IS AM RADIO RECEPTION DIFFERENT DURING THE DAY THAN DURING THE NIGHT?

You then ask:  "What about FM reception?"

Homework assignment:

At the end of the class, students are given a similar challenge to the first one:   overnight, see what the furthest FM station is that they can receive.  Rewards should be given for the furthest station and maybe to most out-of state stations found.   (There are typically too many in-state stations to play without that restriction.)

 

TEACHERS' EXPERIENCES

  • "This was one of the more amusing days.  When I asked the students 'Why is AM radio reception different during the day than during the night?', I got responses ranging from:  'There is less moisture in the air' to 'There are fewer AM radios turned on to suck up the radio waves'."  -Jeffrey Yuhas, Reading (MA) Memorial High School
 
 
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