Lord Kelvin was thereby induced to identify magnetic force with rotation, involving, therefore, angular momentum in the aether.
It is necessary that the aperture of the pupil be accommodated to the angular extent of the spectrum, or reciprocally.
But if it be possible to mount a fixed telescope by which a solar or stellar image can be formed within a laboratory we give the following advantages: - (1) There is no mechanical limit to the length of the telescope; (2) the clockwork and other appliances to move the mirror, which reflects the starlight along the axis, are much lighter and smaller than those required to move a large telescope; (3) the observer remains in a fixed position, and spectroscopes of any weight can be used on piers within the laboratory; and (4) the angular value of any linear distance on a photographic plate can be determined by direct measurement of the distance of the photographic plate from the optical centre of the object-glass.
In finding the position in which the bob will revolve with a given angular velocity, a, for most practical cases connected with machinery the mass of the rod may be considered as insensible compared with that of the bob.
Msh2(n-a); (3) so that this ellipse can be rotating with this angular velocity R for an instant without distortion, the ellipse a being fixed.
The basement storey has the same number of faces formed into convex flutes which are alternately angular and semicircular.
For we have seen that r is constant when there are no extraneous forces; and r is evidently not affected by an instantaneous impulse which leaves the angular momentum Cr, about the axis of symmetry, unaltered.
The development from the angular to the curved shape of S may be seen in its occurrences on the early cippus found in the Roman Forum in 1899.
It should be noticed that clocks, on which Tycho Brahe depended very little, were used at Cassel for finding the difference of right ascension between Venus and the sun before sunset; Tycho preferred observing the angular distance between the sun and Venus when the latter was visible in the daytime.
In the ancient astronomy the anomaly was taken as the angular distance of the planet from the point of the farthest recession from the earth.