Consider an object of mass m suspended from a spring scale attached to a rigid support. At the Earth's equator, the scale reading, which is the magnitude of the object's apparent weight, equals the magnitude of its true weight minus the magnitude of the centripetal force. However, if the object suspended from the scale is placed at some other latitude λ, then the centripetal force acting on the object is directed towards point P on the rotational axis, away from the Earth's center. Hence, the apparent weight of the object equals the true weight minus the cosine component of the centripetal force directed towards the Earth's center. In general, by dividing the equation by m, the net acceleration g' of the object away from the poles is less than the acceleration due to gravity by a factor equal to the centripetal acceleration. The Earth is an oblate sphere having an equatorial radius greater than its polar radius. Thus, its variable density also contributes to the variation in acceleration due to gravity.