Across
- 1. Thermal energy transferred because of a temperature difference (Bulgarian: пренасяне на топлина, meaning heat transfer)
- 3. The energy transfer pathway via electromagnetic waves; it requires no direct contact (German: Strahlung)
- 5. A rapid back-and-forth movement around a fixed point, important in particle energy transfer (Bulgarian: вибрация)
- 8. The full range of electromagnetic wavelengths and frequencies, or the range of visible light colours (Spanish: espectro visible)
- 10. To bounce radiant energy, light or sound away from a surface rather than absorb it (Spanish: reflejar)
- 12. The number of complete wave cycles per second, measured in hertz (German: Frequenz)
- 13. The variable a scientist deliberately changes in an investigation
Down
- 2. To give off or release thermal radiation from a surface into its surroundings
- 4. To take in radiant energy rather than reflect or transmit it (Spanish: absorber)
- 6. A measure related to the average kinetic energy of particles in a substance (German: Temperatur)
- 7. To spread light or radiation in different directions, as translucent materials can do (German: streuen, meaning to scatter)
- 9. Electromagnetic waves just beyond the red end of visible light, often associated with thermal radiation (Bulgarian: инфрачервени лъчи)
- 11. The SI unit used to measure energy and work