filter capacitors

Can anyone tell me how capacitors remove the ripples from the pulsating dc signal coming out of the rectifier ?

A capacitor is a "device for storing energy in the form of an electrostatic field", essentially it's like a small battery, it charges up during the rectified pulses, and maintains the voltage during the dips. It's important to use one that's big enough to supply the required current, or you get too much ripple.

does placing a capacitor cause phase changes in the pulsating dc?
I mean ,is there output signal during the initial charging of the capacitor ?

dragonwarrior said:

does placing a capacitor cause phase changes in the pulsating dc?
I mean ,is there output signal during the initial charging of the capacitor ?

Click to expand...

During the firstcharging pulse the output will be the same as it's rising edge.

There will always be some ripple with a capacitor filter, the larger the capacitor, the smaller the ripple for a given load current. When the pulsating DC source voltage is above the capacitor voltage, the capacitor is charging with current going into the capacitor from the DC source. During this time the DC source is also powering the load. When the DC source voltage is below the capacitor voltage, then the current starts flowing out of the capacitor (capacitor is discharging) and the capacitor is providing all the current to power the load.

A capacitor is the electronic equivalent of a bucket with a big spout at the bottom.

The rectifier is the electronic equivalent of a hand pump that pulses every time you push down in the handle.

One the capacitor is full of charge or the bucket is full of water, electricity keeps flowing out of the capacitor somewhat smoothly like the water flows out of the spout in spite of the fact that water is being delivered one pump at a time.