gravity must be considered more carefully as it is acting in the plane of the circular path
equation can still be used when speed is constant, very rare in real-world scenarios - objects tend to slow down on the way up and speed up on the way down
Fc is a net force - it requires other forces
Inside the top
Draw vector diagram of forces
Towards centre = positive, Away = negative
Find expression for FC
Fc = Fg + Fn
can be normal force or tension if attached to string or wire → Fc = Fg + Ft
If Fg > Fc, the object will fall, so to stay up ac > 9.8, so centripetal acceleration must be more or equal to 9.8
at minimum possible speed, Fn = 0
v = √rg
no reaction force if there is no surface - so it is tension of a string
Outside the top
the direction of the normal force is away from the centre
Fc = Fg - Fn
centripetal force reduces normal force
Fn = Fg - Fc
as v ⬆️ Fn ⬇️ - ⬇️ apparent weight in these situations
If Fc is bigger than Fg, the object will go flying straight off
Inside the Bottom
direction of the weight force is away from the centre
Fc = Fn - Fg
centripetal force increases normal force (or tension)