Answer: Nuclear transitions (radioactive decay).
- A Nuclear transitions (radioactive decay)
- B Ordinary chemical reactions such as combustion
- C Electrons accelerating and decelerating in a metal target
- D Thermal emission from objects at everyday temperatures
Correct answer: A. Nuclear transitions (radioactive decay)
Explanation: Gamma rays are emitted during nuclear reactions and radioactive decay when the nucleus transitions from an excited to a lower energy state. They have the highest energy EM radiation.
In an electromagnetic wave, the oscillating electric field (E) and magnetic field (B) are perpendicular to each other and to the direction the wave travels - a purely transverse wave that needs no medium, unlike sound.
Concept context
Maxwell's equations, EM spectrum, properties, and applications of each band.