The current is limited by the reactance of the 10 uF capacitor. The maximum current is 1 amp. What is reactance?
Reactance is just like resistance but it doesn't waste power when limiting the current like a resistor does. Higher the capacitance of the capacitor or the frequency of voltage source, lower the reactance thus higher the maximum current.
This is a very cheap way to create a low current source from mains voltage but at the same time it can be dangerous.
