Two experiments are conducted are conducted to determine the mass of an object. in experiment 1, the object's weight is measured by using an electronic balance once the object has been placed at rest on the balance. in experiment 2, the object is pulled along a horizontal surface with a spring scale such that the force reading on the spring scale remains constant while a motion detector is used to measure the instantaneous speed of the object as it is pulled. all frictional forces for both experiments are considered to be negligible. which of the two experiments, if either, could be used to determine the gravitational mass of the object?