Which atmospheric force retards forward motion?

Which atmospheric force retards forward motion?

• A. Friction
• B. Pressure gradient force
• C. Coriolis force
• D. Buys Ballot's law

Answer: (A)

Friction is the drag between the moving air and the Earth's surface. Near the ground, this friction acts opposite to the wind’s direction, slowing it down and dissipating kinetic energy as heat. Because the wind slows where friction is strong, the effective influence of the Coriolis force lessens there, so surface flow tends to cross isobars toward lower pressure. The pressure gradient force is what would push air from high to low pressure and accelerate it, while the Coriolis force deflects the wind without inherently slowing it. Buys Ballot's law is a rule about wind direction relative to pressure systems, not a force acting on the air. So friction is the force that retards forward motion.

Friction is the drag between the moving air and the Earth's surface. Near the ground, this friction acts opposite to the wind’s direction, slowing it down and dissipating kinetic energy as heat. Because the wind slows where friction is strong, the effective influence of the Coriolis force lessens there, so surface flow tends to cross isobars toward lower pressure. The pressure gradient force is what would push air from high to low pressure and accelerate it, while the Coriolis force deflects the wind without inherently slowing it. Buys Ballot's law is a rule about wind direction relative to pressure systems, not a force acting on the air. So friction is the force that retards forward motion.