Vocab Crossword

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Across
  1. 5. fast in one direction
  2. 6. energy in motion
  3. 7. objects hitting each other
  4. 8. fast
Down
  1. 1. apply force
  2. 2. taking up space
  3. 3. push or pull
  4. 4. rubbing hands
  5. 7. leads to change
  6. 9. detaches from spacecraft