Value Of e/m

The purpose of this experiment was to study the magnetic field of the Helmholtz coils in the form of electron trajectories and determine the value of e / m. Determining the value of e / m is done by measuring the diameter of a circle using a scale measuring the electron trajectories contained in the unit for the Helmholtz potential difference constant, strong flow of coil turns and the potential difference changes, strong constant coil current. The calculation of the value of e / m done analytically and graphs. The value of e / m with analytical calculations and graphs during the constant potential difference, strong currents changed each coil is 3.07 x 1011C / kg and 4.30 x 10 11C / kg, while at constant coil current and potential difference change the value of e / m respectively are 2.60 x 1010 C / kg and 1.46 x 10 11C / kg. By reference to the value of e / m is 1.76 × 1011 C / kg (Beiser, A.1990).