Time Zones

I just spent about 8.5 hours flying from Philadelphia Pennsylvania to Anchorage, Alaska a span of four times zones.  It is exhausting because of having left so early in the morning and arriving at my destination mid afternoon. 

Its interesting that the world is divided into a minimum of 24 time zones based on the idea that each time zone is 15 degrees from the next time zone or about an hour apart but in reality it does not quite work that way. There is the GMT line or Greenwich Mean Time, the International Date Line which have added a couple of extra time zones to everything.  Then there are a some places such Singapore or  North Korea as which only have 30 or 45 minutes in the time zone. 

One large country, China, only has one time zone. China has operated on Beijing Time or Chinese Standard Time since 1949 when the communists took over.  A question asking about travel time in China would require no additional time zone calculations but if you flew to Singapore, you'd have to keep in mind the 30 minute time zone.

There are several sites which provide some very good time change problems complete with explanations and very real problems.  For instance, Space Math by NASA takes time to explain the time zones in the United States but its problems deal with what time astronomers need to be ready to watch a solar flare.  I've actually done some calculations like that to determine if I could watch a solar event.

Berkley has a nice set of problems which take this a step further by involving more countries after having students practice finding times when going from one time zone to another.  The questions require students to calculate differences between Central Australia and Alaska or Universal Time and California.

I was unable to find problems in which the traveler began in Germany and ended in one of the countries with a 30 or 45 minute time zone.  I think it would be cool to have students create a a trip through certain countries with information on time zones, take off and landing times for a realistic activity.

Let me know what you think.  I'd love to hear from you. 

Time Zones and Math

Today's post came in the middle of my trip.  I am on my way to Michigan and as I checked my itinerary I discovered a beautiful warm up problem.

The warm up question is "How can I leave Grand Rapids, MI and arrive in Chicago, IL, one minute apart?"  To answer this question, a student needs to know the two cities are in  two different time zones in addition to being in two different states.  I could even ask how long the trip is between the two cities. 

  Any questions involving travel and time zones require students to use higher order thinking skills because of the time zones involved.

Another problem I could ask would be "If you take off from Honolulu, Hawaii at 9:30 PM and the trip is 5 1/2 hours long, at about what time would you land in Anchorage, Alaska?  This requires students to know that Alaska is two time zones ahead of Hawaii during the summer.  If the trip happens in winter, the time change is only one hour.

Which brings us to the fact that only two states and part of another state do not participate in daylight savings time, so if you asked a question involving one of those places, it could add another twist to the problem.

I think that I could look up some real flight schedules for various airlines and have students calculate the flight time so they know about how long the flight will be based on the information given.

So many possibilities.  I am already planning on using these types of problems.