Physics307L F08:Labs/e over m

Initial notes
Setup according the exisiting 307L manual.

Room lights need to be off for this one.

The electrical setup for this lab is extensive. Three different power supplies are required as well as a couple multimeters. We seem to have enough power supplies, but we're not sure whether we're missing the "perfect" power supplies, because of requirements for specific and non-standard voltages (such as 6.3 V).

4 cm (maybe 3.9) on the left hand side, 4.5 cm on the right side; 300 V accelerating; 1.2 amps for helmholtz coils;

Some considerations not taken in the lab manual is the affect of the focus and the heater voltage on the electron velocities coming out of the electron gun. What focus and heater voltage do you think is optimal and why? Consider taking measurements at what you think is the optimal settings and then taking some quick and dirty measurements with a different focus. Are the measurements better or worse?

Several people have brought up the point of the earth magnetic field and its effects on the experiment. Is this a potential problem? What about the magnetic field of the surrounding voltage sources?