the axis acts against and it would be a contact force
It is an example of reflection of wave. C.
Answer:
when an electron made a transition from an outer orbit to one closer to the nucleus
Explanation:
Bohr amended that view of the motion of the planetary electrons to bring the model in line with the regular patterns (spectral series) of light emitted by real hydrogen atoms. ... Light, he proposed, radiated from hydrogen atoms only
<span>Science is orderly knowledge proven by experimentations.</span>
<u>Answer:</u>
Yes
<u>Explanation:</u>
Average velocity is the ratio of total displacement and time taken for that displacement:

This means if displacement is zero, then average velocity will also be zero.
Displacement is zero when an object moves some distance in one direction, and then moves the same distance but in the opposite direction.
∴ As it is possible for displacement to be zero, it is also possible for average velocity to be zero.