Question

The Geostrophic wind represents a balance between the Coriolis force and which other force?

• A. Gravitational force
• B. Frictional force
• C. Pressure gradient force
• D. Centrifugal force

Hint:

\textbf{Geostrophic wind = PGF balanced by Coriolis force}.
Flows parallel to isobars.

Answer 1

The Correct Option is C

Concept: Geostrophic wind is an idealized wind that flows parallel to isobars in the upper atmosphere, where friction is negligible.
Step 1: Understanding forces acting on wind.
Air motion is influenced by several forces, mainly:

• Pressure gradient force (drives air from high to low pressure)
• Coriolis force (deflects motion due to Earth's rotation)

Step 2: Condition for geostrophic balance.
Geostrophic wind occurs when: \[ \text{Pressure gradient force} = \text{Coriolis force} \]
Step 3: Eliminating incorrect options.

• Gravitational force acts vertically, not in horizontal wind balance.
• Friction is negligible in geostrophic conditions.
• Centrifugal force is involved in gradient wind, not pure geostrophic wind.

Conclusion:
Thus, the correct answer is Pressure gradient force.