Regarding the concept of pressure gradient and its role in wind motion, which of the following statements are correct?

Concept overview / definition Pressure gradient is introduced in climatology to explain why winds can be gentle in some situations and very strong in others. It refers to how quickly pressure changes over a given horizontal distance, not just the absolute values at individual points. If the pressure difference between two places is large over a short distance, the pressure gradient is steep; if the difference is small or spread over a long distance, the gradient is weak, and this directly influences wind speed.

Why the correct option is correct Statement 1 is correct because the teacher defines pressure gradient as the rate of change in pressure per unit horizontal distance. Statement 2 is correct since a larger difference such as from 100 to 20 units over a given distance creates a stronger push on the air, so winds move with greater speed. Statement 3 is also correct because when the pressure gradient is very small the driving force is weak, so winds tend to remain light or gentle. All three statements together summarise the link between pressure pattern and wind motion described in the lecture.

Why the other options are incorrect Any option that omits one of these statements fails to reflect the full explanation of pressure gradient given in the discussion. The class example clearly connects the magnitude of pressure difference with the strength of wind, and also notes that a small gradient leads to slower motion. Options that deny the role of rate of change, or that imply wind speed is unaffected by the sharpness of the gradient, are inconsistent with the step by step reasoning used in the transcript.

UPSC exam tip / common confusion In exam questions on wind speed, students sometimes focus only on the absolute values of pressure at two points and ignore the distance between them. A safer approach is to think in terms of per unit horizontal distance, just as the definition of gradient suggests. When comparing two diagrams, the one where isobars are closer together usually indicates a steeper pressure gradient and therefore stronger winds. Remember this visual shortcut when interpreting synoptic charts in prelims questions.