Imagine that the standard kilogram is placed on Earth's equator, where it moves in a circle of radius 6.40 x 106 m (Earth's radius) at a constant speed of 465 m/s due to Earth's rotation.
(a) What is the magnitude of the centripetal force on the standard kilogram during the rotation? Imagine that the standard kilogram hangs from a spring balance at that location and assume that it would weigh exactly 9.80 N if Earth did not rotate.
(b) What is the reading on the spring balance; that is, what is the magnitude of the force on the spring balance from the standard kilogram?