Question

The earth rotates from west to east. A wind mass begins moving due north from the equator, along the earth’s surface. Neglect all effects other than the rotation of the earth. What will happen to the wind mass?
\[{\text{A}}{\text{.}}\] Always move due north
\[{\text{B}}{\text{.}}\] Shift a little to the east as it moves to higher latitudes
\[{\text{C}}{\text{.}}\] Shift a little to the west as it moves to higher latitudes
\[{\text{D}}{\text{.}}\] Move along a loop and return to its starting point on the equator

Answer 1

Hint- Here, we will proceed by defining the term wind mass used in meteorology. Then, we will discuss the linear velocities of the points on the surface of the earth. Finally, we will see the effect of rotation of earth on the wind mass.

Complete step-by-step solution -
In meteorology, wind mass is an air volume determined by its temperature and the amount of water vapour. masses span several hundreds or thousands of miles, and conform to the surface properties below them. They are categorized by latitude and by their regions of continental or maritime origin. Colder wind masses are called arctic or polar while warmer wind masses are considered tropical. Continental and superior wind masses are dry while the wind masses of maritime and monsoon are hot. Climate distinguishes wind masses with characteristics of different densities (temperature or moisture). When wind mass moves away from its source area, the underlying vegetation and water can change its character quickly.
As the earth rotates about its own axis from west to east, all the points which lie on the surface of the earth exhibit the same angular velocity as acquired by the earth whereas the linear velocities are different at different points on the surface of the earth. The linear velocity is maximum at the equator and as we move towards higher latitudes, it decreases.
Due to the rotation of the earth from west to east, a velocity towards east is given to the wind mass. The wind mass usually moves northwards from the equator and due to the eastward velocity imparted to the wind mass, the wind mass shifts a little to the east as it moves to higher latitudes.
Therefore, option B is correct.

Note- The earth rotates from west towards east because the sun rises in the east and sets in the west. It is nearly impossible to slow down the rotation of the earth because the law of conservation of angular momentum is valid for the whole universe and for this law to be valid, the universe should be in motion constantly.