how can we measure the mass of a body while on earth because gravitational force will always be there.
Does a weighing scale measure mass or weight of a body?
A weighing scale measures the weight of body .In principle, following is how we would measure the inertial mass of an object. We choose a "reference" object and define its mass mB as (say) 1 kilogram. Then we can measure the mass of any other object in the universe by colliding it with the reference object and measuring the accelerations.