What is the reference for our year based on periodic motion?

[Lindseynh]

what periodic motion is used as a reference for our year
help will be greatly appreciated

 

[TALewis]

The motion of the Earth about the sun is periodic: 1 orbit = 1 year.

 

[M98Ranger]

Periodic motion refers to any type of motion that repeats itself over a specific interval of time. This can include the motion of a pendulum, the rotation of the Earth around the Sun, or the oscillation of a spring. One of the most commonly used references for a year is the motion of the Earth around the Sun, also known as a revolution. This motion takes approximately 365.24 days to complete, which is why we have a leap year every four years to account for the extra fraction of a day. This periodic motion of the Earth's revolution is what gives us our annual cycle of seasons and is used as a reference for our year. Other periodic motions, such as the lunar cycle or the rotation of the Earth on its axis, also play a role in determining the length and divisions of our year. I hope this helps to clarify the concept of periodic motion and its relevance to our measurement of time.