The total sum of forces in circular motion in gravitational field

[J.Asher]

Hello,

I am now studying centripetal force.

and the problem is that centripetal force in gravitational field.

Let's talk about Ferris-wheel ride, this ride has some rooms to carry people and fixed to the

edge of the wheel. Since it is rotating periodically, its magnitude of net force has to be

mv^2/r, right?

but this is the sum of forces. now I cannot go further.

I cannot fully understand how the force will be summed up into the net centripetal force.

Is there anyone who can help me by telling me the how the sum of the forces can finally

have the net centripetal force mv^2/r ,

(the forces might be normal force and gravitational force, right?)

waiting your answers.. thanks for reading

 

[haruspex]

Think about this: how is the chair attached to the Ferris wheel?