If the speed of rotation of the Earth increases, the weight of the body would decrease. This is because the weight of an object is the force exerted on it due to the gravitational attraction between the object and the Earth. The force of gravity depends on the mass of the object and the mass of the Earth. However, the weight of an object also depends on the centrifugal force caused by the rotation of the Earth. When the Earth rotates faster, the centrifugal force increases. This centrifugal force opposes the force of gravity, making the effective gravitational force on the object slightly smaller. As a result, the weight of the body is slightly reduced. It is important to note that this decrease in weight would be very small and would not be easily noticeable.