Serious answer from a physicist required (please no random answers) Had an argument in the pub tonight whether 2 objects of equal size and shape one 5kg and one 100000 kg would fall from a height of 40k feet and hit the ground at the same time or not? This would happen in perfect lab conditions i.e. no weather but in air. I won’t say in which direction I argued please provide an answer with working/proof. Note that perfect lab conditions does not indicate a vacuum just no external factors other than still air or another arbitry gas i.e. with a mass that could provide a frictional force. Cheers D P.S. please provide worked proof!