While weight of a body depends directly on acceleration due to gravity g, the value of g depends upon many factors. It depends on the shape of the Earth, rotation of the Earth, etc. Weight of a body at a pole is more than that at a place on equator because g is maximum at poles and minimum on equator. Acceleration due to gravity g varies with latitude lambda according to the equation g_x = g - R omega^2 cos^2lambda, where R is radius of Earth and omega is angular velocity of Earth. A body of mass m weighs W_r in a train at rest. The train then begins to run with a velocity v around the equator from west to east. It conserved that weight W_m of the same body in the moving train is different from W_r"Let "v_e be the velocity of a point on equator with respect to axis of rotation of Earth and R be the radius of the Earth. Clearly, the relative velocity between Earth and train will affect the weight of the body. Difference between weight W_r and the gravitational attraction on the body can be given as