Forces at Work: teacher key

Pushes and Pulls, grade 1 edition, written for 1st grade. Balls, boxes and sleds all move when forces push or pull them. See what forces do, and what gravity and friction do.

Read the book. Print this page for the key.

Questions and answers

1. What does a ball do until a push or pull moves it?
   • Rolls away
   • Stays still (answer)
   • Jumps up
2. Which one moves less with the same push?
   • A heavy box (answer)
   • A light box
   • Both the same
3. Why does a dropped ball go down?
   • Friction rubs it
   • It is light
   • Gravity pulls it (answer)
4. What does friction do to things that slide?
   • Slows them down (answer)
   • Speeds them up
   • Turns them
5. What can a force make a thing do?
   • Only stand still
   • Only get heavy
   • Speed up, slow down or turn (answer)

Words

• force: push or pull
• direction: which way
• gravity: pull toward Earth
• friction: slowing rub