A number of balloons are attached to a circular disk with string. Some balloons are filled with air and some balloons are filled with helium. The disk is hung freely from ceiling of a room and is disk is rotated about its center. Assuming that the disk remains horizontal while rotating, describe what happens to the balloons?
(a) All the balloons move away from the center of the disk.
(b) All the balloons move towards the center of the disk.
(c) Air balloons move outwards away from the center and helium balloon move towards the center.
(d) Air balloons move inwards towards the center and helium balloon move out- wards the away from the center. I am in a doubt that is the centrifugal force will dominating and all balloon goes outside or some special effect(like pressure) will affect to helium balloon to go inside(like the behaviour of helium balloon in a car at a turn)