Science Buddies: "Ask an Expert"

Hi,
I have A DC POWER SUPLY WHICH GIVES 55V.
WHAT SHOULD I DO INORDER TO COVERT THIS VOLTAGE INTO 9V?
PLEASE TELL ME THE TOOLS I NEED TO USE AND THE STEPS TO DO.
I NEED THIS INFORMATION PLEASE IN THE FASTEST WAY YOU CAN SEND ME A REPLY TO [email protected].
I HOPE YOU HELP ME!

There are lots of other factors that you need to consider. Some of them are:
1) How much current or power does your 9 volt load require?
2) How tolerant is your 9volt load to voltage fluctuations?
2) What is the current rating on your 55 VDC power supply?
2) Does efficiency matter?

Crude methods of "regulation" will be less than 17% efficient and produce 83 Watts of heat for every 1 Watt of power delivered to the load. These come from a simple ratio of voltage in to voltage out.

If you have access to AC power and your 9 VDC current load is small enough to be handled by some of these low cost 9 VDC AC adapters, you are probably better off buying one of them instead.