Firs of all, 'storing power' makes absolutely no sense, as power is simply the rate of doing work. What you should be asking is whether you can use a d.c. supply to store energy. And the answer is no! You cannot 'store' energy with a d.c. supply. There is no practical way of storing useful quantities of electrical energy.
dc power supply
When you connect a load (motor, light bulb, etc.) in series with a power supply, current will flow, whether AC or DC depends on the power supply you are using.
DC Power is Direct Current Power Supply.
Almost all digital electronics use a AC to DC power supply. Digital electronics cannot handle AC. all electronics device having battery powered are using DC power supply http://www.wzmicro.com
conclusion of dc power supply 9V
In an ideal DC power supply, there is no ripple.
Because it does not allow ac to pass through it...
DC 12V power supply can convert 110/220V AC power source to 12V DC.
The DC supply may supply power to trip breakers, or to power the protective relays.
Variable dc supply is applicable in loads that are variable.
Variable DC power supplies are commonly used in electronics labs, production lines, and testing environments. They are used to power and test electronic devices such as electrical components, circuits, and sensors. Variable DC power supplies are also used in research and development for prototyping and experimenting with different voltage levels.
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