Answer:
difference:
1. The generation mechanism is different, the mechanical wave is generated by mechanical vibration; the electromagnetic wave generation mechanism is also different, there is the periodic movement of electrons (radio waves); the outer electrons with atoms are generated after being excited (infrared, visible, ultraviolet) The inner electrons with atoms are generated after excitation (roentgen rays); the nuclei with atoms are generated after excitation (gamma rays).
2. The propagation mechanism is different: the mechanical interaction between the particles and the alternating induction of the electromagnetic field.
3. Mechanical waves have both transverse waves and longitudinal waves; electromagnetic waves are material waves and belong to transverse waves.
4. The influence of the medium on the propagation speed is different
Explanation:
https://qiaodahai.com/similarities-and-differences-between-mechanical-waves-and-electromagnetic-waves.html
Answer:
On January 22, 2001, EPA adopted a new standard for arsenic in drinking water of 0.01 mg/l or 10 parts per billion (ppb), replacing the old standard of 50 ppb. Water systems had to meet the new standard by January 23, 2006.
Explanation:
Answer:
Glaciers will only form under certain conditions and in specific environments. A cold climate and sufficient moisture in the air for the precipitation of snow are both necessary factors that permit at least some snow to last year-round. This allows for the build-up and compaction of snow that will eventually become glacial ice. Sufficiently cold climate conditions exist at high altitudes and high latitudes.
Explanation:
There must be landmasses at high latitudes for continental glaciers to occur, as they cannot form over open water. While persistent sea ice can and does form, because it floats, it does not flow as a glacier does.
Finish. The work is done then the work is finish.
