What it shows
Four diodes arranged as a bridge send current through the load in the same direction on both halves of the AC cycle, turning AC into pulsating DC. A capacitor smooths the output.
This idea has a short entry only. For the science behind it, read the sentence above with your textbook and ask your teacher to explain the law or idea it shows, so you can describe it in your own words.
Materials
- Four 1N4007 diodes
- A low-voltage AC supply of 6 to 12 V from the school lab, or a sealed 9 V AC adapter checked by your teacher
- A 1000 µF 25 V electrolytic capacitor (fitted the right way round)
- A 1 kΩ load resistor, or an LED with a 680 ohm resistor in series
- A breadboard and a multimeter
Safety
For this project: Never wire or touch the mains side yourself: use a low-voltage AC supply or a sealed AC adapter from your teacher.
Never use mains electricity: power models with cells, batteries or a low-voltage adapter. Sharp and hot tools, flames and lab chemicals need an adult or your teacher beside you. Keep magnets, button cells and small parts away from young children, and wash your hands after making.
How to go about it
Numbered steps have not been written for this idea yet. Plan it with your teacher: sketch the design with measurements, build one part at a time, test each part, and write every observation with the date. The free ebooks below have step-by-step projects of the same kind.
Free ebooks for this project
Science projects
Investigatory Projects for Class 11 and 12
Topics, method and report structure for physics, chemistry and biology
Robotics
Electronic Components Handbook
Resistors, capacitors, LEDs, diodes, transistors and more, with how to use each
Find out more about physics
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