×

SparkFun will be closed May 25, 2015 for Memorial Day. Orders placed after 2pm on Friday the 22nd will ship out on Tuesday. Thanks!

avatar

ChickMagneto

Member Since: May 23, 2012

Country: United States

  • Haha, nice!

  • Hey Rob I brought you your… Oh, you said soldering gun, gotcha. I’LL BE BACK.

  • Actually I believe it is the fall time, literally. F=ma so when the force is restricted to merely gravity, yes acceleration is constant. These and many other types of coin detectors use a property of conductors and magnetism known as eddy currents. Essentially, on the way down the metal, conducting coin passes a magnet. This magnet induces a current in the conductor, drawing from the force of gravity to push the electrons along. The specific properties of the coin itself, hence the differentiation between coins, determines the conductivity and therefore the amount of force is “stolen” from gravity, making the coin fall slower. Hence the fall time.

  • All of y'all are wrong, it does use a magnet if I’m correct, but it uses a feature of physics known as eddy currents. As any conductor moves in the presence of a magnetic field a current is generated in the conductor. Depending on several factors such as the size and conductivity of the object, such as a coin, it will fall at different rates. It falls slower because some of the gravitational potential energy is utilized to move the electrons. Hope this helps!

  • Bear: You think they’re on to us?? Banana: Relax, they don’t know what the President looks like…

No public wish lists :(