Calcium has 2 valence electrons
Answer: The wave can flip upside down.
Reflection is the bending of a wave when it cannot pass through. For example, plain mirrors which are flat, a ray of light hits the mirror and is reflected from the mirror since it cannot pass through
When reflection occurs the speed and frequency of the wave does not change but the wave is flipped upside down.
The speed does not change because speed is affected by the change in medium the frequency also remains the same since the energy of the wave does not change.
Answer:
An elliptical orbit is the revolving of one object around another in an oval-shaped path called an ellipse. The planets in the solar system orbit the sun in elliptical orbits. Many satellites orbit the Earth in elliptical orbits as does the moon.
Harmonics, Loop and Harmonic number
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