Which of these happens to the wave when it travels from Medium 1 to Medium 2?

its energy increases

its amplitude increases

its frequency decreases

its wavelength decreases

Answer: its wavelength decreases

Explanation: A wave is an oscillating disturbance of some physical magnitude in space and periodic in time. The spatial oscillation is characterized by its wavelength, while the time elapsed in a complete oscillation is called the wave period, and is the inverse of its frequency. Wavelength and frequency are related to the speed with which the wave propagates.