How Fast Is Too Fast to Measure?: teacher key

The Fastest Animals, grade 10 edition, written for 10th grade. Falcons, bats and sailfish move too fast to watch. Here is how researchers work out their speeds.

Read the book. Print this page for the key.

Questions and answers

1. How did the bat study follow whole flights?
   • From a tower with radar
   • From an airplane with radio transmitters (answer)
   • From a balloon with a camera
2. Why are stoops hard to study?
   • Falcons refuse to dive
   • Nobody likes falcons
   • The outcome is often difficult to observe because of the high speed (answer)
3. What does a tucked wing change in a stoop?
   • It reduces roll inertia so the falcon rolls faster (answer)
   • It slows the dive
   • It makes the falcon fly higher
4. Why did sailfish rank lowest after body size was counted?
   • They were slower in the water
   • They were younger
   • They were longer than the other fish and speed rises with length (answer)
5. What does the word median mean here?
   • The fastest value
   • The middle value (answer)
   • The slowest value

Words

• radar: radio tracking
• median: middle value
• erratic: unpredictable
• inertia: resistance to turning