## Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (3rd Edition)

(a) When the two skaters push off from each other, Paula will exert a force on Ricardo. According to Newton's third law, Ricardo exerts an equal and opposite force on Paula. Since the magnitude of the force on each skater is equal and the time of the push-off is the same for both skaters, the magnitude of the impulse exerted on each skater is the same. Therefore, Paula and Ricardo will have the same magnitude of momentum after the push-off. (b) Note that $p = mv$ Since both skaters have the same magnitude of momentum, the skater with less mass must have a greater speed. Since Paula weighs less than Ricardo, Paula will have a greater speed than Ricardo.