# How to use *Axis-of-rotation* in a sentence

The moments of the components of these actions and reactions in a plane to which the

**axis of rotation**is at right angles are the two aspects of the torque acting, and therefore the torque acting on B through the shaft is measured by the torque required to hold A still.The counterpoise w balances the head about its

**axis of rotation**.The

**axis of rotation**AB bears a rigidly attached rod DBC inclined to it at an angle equal to the sun's polar distance.Take rectangular axes, of which Oz coincides with the

**axis of rotation**.It is to be carefully noticed that the axis of resultant angular momentum about 0 does not in general coincide with the instantaneous

**axis of rotation**.AdvertisementHence if the earths

**axis of rotation**deviates slightly from the axis of figure, it should describe a cone about the latter in 320 sidereal days.By reasoning similar to that of 30, it appears that OT is the instantaneous

**axis of rotation**01 the rolling cone.In a turning piece, the perpendicular let fall from its connected point upon its

**axis of rotation**is the arm or crank-arm.The product of the force of friction by the distance at which it acts from the

**axis of rotation**is called the moment of friction.Centrifugal Force of a Rotating BodyThe centrifugal force exerted by a rotating body on its

**axis of rotation**is the same in magnitude as if the mass of the body were concentrated at its centre of gravity, and acts in a plane passing through the**axis of rotation**and the centre of gravity of the body.AdvertisementIf the

**axis of rotation**traverses the centre of gravity of the body, the centrifugal force exerted on that axis is nothing.It is essential to the steady motion of every rapidly rotating piece in a machine that its

**axis of rotation**should not merely traverse its centre of gravity, but should be a permanent axis; for otherwise the centrifugal couples will increass friction, produce oscillation of the shaft and tend to make it leave its bearings.Neglecting the mass of the shaft itself, when the shaft rotates with an angular velocity a, the centrifugal force Wae/g will act upon the shaft and cause its axis to deflect from the

**axis of rotation**a distance, y say.Its determination is difficult, because it is involved with questions of the changing orientation of the earth's

**axis of rotation**.This plane remains invariable so long as no third body acts; when it does act the position of the plane changes very slowly, continually rotating round the radius vector of the planet as an instantaneous

**axis of rotation**.AdvertisementThere is also a libration in latitude, arising from the fact that the

**axis of rotation**of the moon is not precisely perpendicular to the plane of her orbit.These appearances he referred with great acuteness to the slight inclination of the sun's

**axis of rotation**to the plane of the ecliptic. Thus, when the earth finds herself in the plane of the sun's equator, which occurs at two opposite points of her orbit, the spots, travelling in circles parallel with that plane, necessarily appear to describe right lines; but when the earth is above or below the equatorial level, the paths of the spots open out into curves turned downwards or upwards, according to the direction in which they are seen.The latter is defined by the condition that its plane makes a right angle with the earth's

**axis of rotation**.The

**axis of rotation**of the Earth always points to the same direction, toward the north celestial pole.Precession The

**axis of rotation**also precession The**axis of rotation**also precesses, that is it describes a circle in the sky every 51 000 years.AdvertisementAnother web is fixed parallel to the axis of the screw, as nearly as possible in the same plane with it and passing through the

**axis of rotation**of the micrometer.To use the instrument, it is well first to adjust the web moved by the screw S, so that its point of intersection with the web (commonly called the " position-web "), which is parallel to the axis of the screw, shall be nearly coincident with the

**axis of rotation**of the micrometer box.Now direct the telescope to a star near the equator and so that the star's image in its diurnal motion shall pass across the intersection of the two webs which mark the

**axis of rotation**of the micrometer box.In the Robinson anemometer the

**axis of rotation**is vertical, but with this subdivision the**axis of rotation**must be parallel to the direction of the wind and therefore horizontal.Thus is determined the position of the centre of percussion C, corresponding to the

**axis of rotation**0.AdvertisementIt is obvious from this equation that, for an

**axis of rotation**parallel to 0 traversing C, the centre of percussion is at the point where the perpendicular OG meets 0.