No extra effort to throw heavier objects in space?

26) Q: Ben travels to a distant planet. In outerspace, with essentially no gravity, he can throw a baseball (mass = 0.5 kg) and a shot put (mass = 4 kg) at the same speed with no discernable difference in effort. True or false?

A: (False.) According to Newton’s second law, force equals mass times acceleration. If the objects are thrown at the same speed by the same person they must have the same acceleration. For the same acceleration the force exerted by the person’s arm has to be much higher for the more massive object. Gravity, or the lack of it, does not change the fact that the shot put will always be harder to throw. It has more inertia.

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