Faraday's Law


Applet by Wolfgang Christian
  • The Figure on the left hand side of the animation shows a voltmeter connected to a simple circuits. The wires are connected in such a way that the circuit possesses the shape of a rectangle. The vertical wire comprising the right side of the rectangle is capable of sliding along the two horizontal wires to which it is connected. The circuit is immersed in a magnetic field which is perpendicular to the page.
  • The graph on the right hand side of the animation shows the voltage read by the voltmeter as a function of time.
  • The animation repeats it self when the time equals 10.00. The time is displayed in the upper left hand corner of the animation.
  • You may control the motion of the vertical wire in one of two ways:
    • You may drag the vertical wire by checking the box marked "U Drag".
    • You may type in an expression for the motion of the wire in the text field marked x(t)=. Keep in mind the following points if you choose this method:
      • Make sure that the box marked "U Drag" in unchecked.
      • The x axis points to the right as usual. The coordinate x=0 lies midway along the length of the horizontal wires. The coordinate x=8 corresponds to the right ends of the horizontal wires. x=-8 corresponds to the x coordinate of the left vertical wire.
      • If you wish to keep the right vertical wire stationary, then type in a value between -8.0 and 8.0 in the text field.
      • Use t for the time variable.
      • Use an asterisk, i.e. *, to denote multiplication. For example, the animation will fail to recognize the expression 2.0+3t, but the animation will recognize the expression 2.0+3.0*t. The text field will become red if you enter an expression that it does not understand.
      • You may use the trigometric function sin and cos in your expression. For example, you may enter the expression 1.0+3.0*sin(pi*t/3.0) into the text field for x(t)=.
      • Use pi to denote the constant 3.14....
  • The magnetic field:
    • The magnetic field is perpendicular to the screen.
      • Red regions containing minus signs denotes areas in which the magnetic field is into the screen.
      • Blue regions containing plus signs denotes areas in which the magnetic field is out of the screen.
    • You may enter an expression for the magnetic field into the text field marked B(x,t)=. Keep in mind the following points while doing this:
      • You may use the trigometric function sin and cos in your expression. For example, you may enter the expression 1.0+3.0*sin(pi*x/2.0)*sin(pi*t/3.0) into the text field.
      • Use pi to denote the constant 3.14....
      • Use t for the time variable and x for the x variable.
      • The x axis points to the right as usual. The coordinate x=0 lies midway along the length of the horizontal wires. The coordinate x=8 corresponds to the right ends of the horizontal wires. x=-8 corresponds to the x coordinate of the left vertical wire.