Question

Which of the following is not in periodic motion​

Answer 1

Answer:

The reason why we only see ~118 elements is because we only see the ones stable enough to observe. Anything common in nature would need to have a half-life comparable to the age of the earth (or be produced as a decay product of something else that does).

Explanation:

PLEASE SHARE THE DIAGRAM

Answer 2

Answer:

. Rotation of the earth about its axis: The rotation of earth about its axis is periodic because it repeats after a regular interval of time. The rotation of earth about a fixed point, hence its motion is not SHM.