Earth's Rotation and Revolution

Practice flashcards covering the Earth's rotation, revolution, axial tilt, Coriolis effect, and orbital mechanics.

What are the two primary motions of the Earth and how long does each take?

The Earth performs rotation on its axis, which takes about $24\,\text{hours}$, and revolution around the Sun, which takes about $365\,\text{days}$ and $6\,\text{hours}$.

What are the specific angles of inclination for the Earth's axis?

The Earth's axis is tilted at an angle of $23.5^{\circ}$ relative to the vertical line from its orbital plane, making an angle of $66.5^{\circ}$ with the plane of the Earth's orbit.

What is the 'Coriolis force' and its alternative name described in the text?

It is an apparent force caused by the Earth's rotation that deflects winds to the right in the Northern Hemisphere and to the left in the Southern Hemisphere, also known as 'Ferrel's Law'.

How are 'Perihelion' and 'Aphelion' defined in relation to the Earth's orbit?

Perihelion is the position where the Earth's distance from the Sun is minimum (approximately $147\,\text{million km}$), while Aphelion is the position where the distance is maximum (approximately $152\,\text{million km}$).

What is the 'circle of illumination'?

The circle of illumination is the travelling boundary that divides daylight and darkness on the surface of the Earth.