Question

20 (a) Replace the following with a word or phrase

air in motion.

Answer 1

Wind refers to the air in motion.

• When the sun heats one section of the atmosphere differently from another, wind forms. As the temperature rises, the air expands.
• The pressure of hot air is lower than that of colder air. Air pressure is constantly changing from high to low.
• Thus, the wind is the movement of air.