Around the World

1
Around the World

• Circles (and spheres) are fairly common, so p
  appears in many real world problems
• If the front tire of a motorcycle has a diameter
  of 50 cm (0.5 m), how many revolutions will it
  make if it is  pushed 1 km to the nearest gas
  station?
• What is the circumference of the motorcycle tire?
• How many circumferences of the circle are there
  in 1000 meters?

2
Around the World

• In the novel Around the World in 80 Days, written
  by Jules Verne in 1873, Phileas Fogg made a
  bet that he could circumnavigate the globe in 80
  days

• What modes of travel were available to him at
  that time?
• What must his average speed be in order to meet
  this deadline?
• The diameter of Earth is 8000 miles. How far
  must he travel?
• C pd so he must go at least 8000p miles (
  25,133 miles)
• Divide 8000p miles by 80 days, or 100p miles per
  day ( 314.16)
• Divide 100p miles per day by 24 to get miles per
  hour ( 13 mph)

3
Around the World

• Zach wants a circular table so that 12 chairs,
  each 16 inches wide, can be placed around it with
  at least 8 inches between chairs.
• What should be the circumference of the table?
• What should be the diameter of the table?
• Will the table fit in a 12-by-14-foot dining
  room?
• A satellite is in a nearly circular orbit 2000 km
  above Earths surface. The radius of Earth is
  approximately 6400 km. If the satellite completes
  its orbit in 12 hours, calculate the speed of the
  satellite in kilometers per hour
• What is the radius of the satellites orbit?
• What distance does it travel in one orbit?
• Distance rate time, what do you need to
  calculate?