空气动力学

• 穴(row; gap)RADICAL
• 工(craftsman; work)PHONETIC

An empty cave with nothing inside is just hollow space.

• 气(vapor; gas; steam)ASSOCIATIVE

The character depicts wisps of vapor rising upward, symbolizing invisible atmospheric air.

• 云(cloud)PHONETIC
• 力(strength; power)RADICAL

Powerful strength like rolling clouds surge creates motion.

• 力(strength; muscle)ASSOCIATIVE

The character 力 depicts a flexed arm muscle, symbolizing strength and power.

• ⺍(two hands (indicating learning))ASSOCIATIVE
• 冖(roof; house)ASSOCIATIVE
• 子(child)RADICAL

A child sitting under a roof with two hands diligently studying represents learning.