1. dna
  2. rocket
  3. bounce
  4. magnet
  5. pendulum
  6. system
  7. research
  8. gravity
  9. compass
  10. balance
  11. molecule
  12. flask
  13. pulley
  14. buoyancy
  15. hourglass
  16. reaction
  17. balloon
  18. blood
  19. force
  20. scale
  21. drug
  22. atom
  23. meteor
  24. sound
  25. experiment
  26. dropper
  27. cylinder
  28. flask
  29. telegraph
  30. satellite
  31. planet
  32. rotate
  33. raining
  34. hydraulic
  35. relativity
  36. ecology
  37. photosynthesis
  38. wind energy
  39. light bulb
  40. test tube
  41. eco energy
  42. paper plane
  43. turning fork
  44. specular reflection
  45. science book
  46. test tube
  47. outer space
  48. bunsen burner
  49. solar system
  50. archimedes principle
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