Across
- 4. the length of one wave cycle
- 6. air currents caused by the expansion and rising of air as it warms and the movement of cooler air to replace it
- 8. the joining together of atoms to produce nuclear energy
- 14. when expanded warm liquid or gas rises above a cooler liquid or gas
- 15. the energy contained in an elastic material that has been stretched or compressed from its original shape
- 18. the kinetic energy of sound waves
- 20. the splitting of atoms to produce nuclear energy
- 21. the number of cycles of a wave pattern that occur in one second
- 22. the energy of motion
- 23. a device that combines hydrogen and oxygen, without combustion, to generate electricity
- 25. the capacity to do work
- 27. energy from sources that will eventually be used up and cannot be replaced
- 28. solar cells that convert the sun's energy directly into electrical energy
- 29. fuels created from plant or biomass sources
Down
- 1. the movement of electrons from atom to atom
- 2. when heat energy passes through a solid
- 3. materials that obey Hooke's Law, which states that the amount a spring extends is proportional to the force with which you pull it
- 5. the energy associated with the Earth's gravitational field; the natural force of attraction created by an object that draws other objects toward itself
- 7. energy from sources that will always be available
- 9. particles released by unstable nuclei when an atom tries to become stable
- 10. energy locked away in different kinds of substances; often released by burning
- 11. energy that is derived from an object's position or condition
- 12. energy from the heat at Earth's core
- 13. electricity generated from moving water over turbines connected to electric generators
- 16. energy that travels in waves from the sun
- 17. energy that occurs as a material heats up and its atoms become more active
- 19. energy from plants
- 24. energy an object has because it is moving
- 26. energy that occurs when the atoms of certain elements are split or fused together