I was learning about wind from my class textbook. In that there is first a description of forces affecting the velocity and direction of wind followed by that is geostrophic wind.
My question is:
At one instance it is written that Coriolis force acts perpendicular to the pressure gradient force and in the next paragraph it is written that ...the pressure gradient force is balanced by the Coriolis force....
If two vectors are perpendicular to each other then they are independent and so do not affect each other.
Following are the images of my text book:
In the figure, horizontal pressure gradient force and Coriolis force are opposite to each other, but since pressure gradient force and Coriolis force are perpendicular so the component of pressure gradient force in direction of Coriolis force must be zero.
Please help me understand which of the two highlighted(red) text is true. Or if both are true and I am making some mistake then kindly clarify.