Question

question 1
the____acts to reduce the speed of air.
a pgf = pressure gradient force
b cf = coriolis force
c fr = frictional force
d gr = gravitational force

question 2
the____acts to accelerate air horizontally from rest.
a pgf = pressure gradient force
b cf = coriolis force
c fr = frictional force
d gr = gravitational force

Explanation:

• Question 1: Frictional force acts against the motion of air, reducing its speed. Pressure - gradient force (PGF) causes air to move from high to low pressure, Coriolis force (CF) deflects moving air (does not reduce speed), and gravitational force (GR) acts vertically (not mainly on air speed reduction).
• Question 2: Pressure - gradient force (PGF) is the force that causes air to accelerate horizontally from rest. It is the force due to the difference in pressure between two regions. Coriolis force acts on already - moving air (deflects it), frictional force decelerates air, and gravitational force acts vertically.

Answer:

• Question 1: C. FR = Frictional Force
• Question 2: A. PGF = Pressure Gradient Force