3.12.1.4 Principle of Millikan’s determination of the electronic charge, e (A-level only)
Content
Condition for holding a charged oil droplet, of charge Q, stationary between oppositely charged
parallel plates.
QV d = mg
Motion of a falling oil droplet with and without an electric field; terminal speed to determine the
mass
and the charge of the droplet.
Stokes’ Law for the viscous force on an oil droplet used to calculate the droplet radius.
F=
Significance of Millikan’s results.
Quantisation of electric charge.
, TURNING POINTS NOTES
3.12.2.2 Significance of Young’s double slits experiment (A-level only)
Content
Explanation for fringes in general terms, no calculations are expected.
Delayed acceptance of Huygens’ wave theory of light