Let x=0 be the beginning of the magnetic field. Express the area (A), and express vw in terms of the area. Then what is vBw in terms of magnetic flux? The magnetic force on the conducting charges is an EMF, an electromotive force. Use these to derive the following expression for the EMF: dm E = dt There should be a minus sign, but let's not worry about that for now. B = 0.05 T (into the board) Frictionless Conducting RailsX X X × × X X¡ × _× × X X X X X X × X X X X X X X хххх хххx х,ххх X X Xx X, × X X v = 300 m/s X X X X хххх хх x|x хххх хххх X X Xx × X X X X XI X X X= X, + vt Frictionless Conducting Rails. MR=100 0 w = 2/3 m

Let x=0 be the beginning of the magnetic field. Express the area (A), and express vw in terms of the area. Then what is vBw in terms of magnetic flux? The magnetic force on the conducting charges is an EMF, an electromotive force. Use these to derive the following expression for the EMF: dm E = dt There should be a minus sign, but let's not worry about that for now. B = 0.05 T (into the board) Frictionless Conducting RailsX X X × × X X¡ × _× × X X X X X X × X X X X X X X хххх хххx х,ххх X X Xx X, × X X v = 300 m/s X X X X хххх хх x|x хххх хххх X X Xx × X X X X XI X X X= X, + vt Frictionless Conducting Rails. MR=100 0 w = 2/3 m