for points outside the sphere,
|
(2)
|
Now, by 'Electricity and Magnetism,' § 634, T the kinetic energy
,
in our case,
.
Now
.
substituting for F and
,
since the term
,
evidently vanishes.
Transforming to polars and taking the axis of x as the initial line, the above integral
.
|
|
By transforming to polars, as before, we may show that this
Similarly,
;