Where a Day Begins: teacher key

Day and Night, grade 10 edition, written for 10th grade. Time zones, a date line that moves, a sun that never sets and a dark that lasts for months. See how people and places live along the edges of day and night.

Read the book. Print this page for the key.

Questions and answers

1. Which country skipped Friday, 30 December 2011, from its calendar?
   • Samoa (answer)
   • Nepal
   • India
2. What did Foucault's swinging bob show?
   • That Earth rotates (answer)
   • That time zones are straight
   • That the Moon pulls tides
3. Why is polar day longer than polar night?
   • Air bends sunlight over the horizon (answer)
   • Earth spins faster at the poles
   • The Moon lights the poles
4. In Longyearbyen, what happens during the polar night?
   • It is pitch dark all day
   • There is nautical polar twilight for part of it (answer)
   • The Sun rises twice
5. How long does the body clock need to adjust after a long flight?
   • About one day for each hour of time-zone change (answer)
   • One hour in total
   • One week for every flight
6. What does nocturnal mean on these pages?
   • Active at night (answer)
   • Living at the poles
   • Measured by stars

Words

• meridian: line of longitude
• solstice: extreme day
• twilight: glow without Sun
• equinox: equal day, night
• nocturnal: active at night
• hemisphere: half of Earth