Question

If every person on Earth picked up a hammer simultaneously, and raised it to approximately their height, would the total mass of the planet increase?

If so by approximately how much?    Please state your assumptions clearly and show your work.

Answer 1

If every person on Earth picked up a hammer simultaneously, and raised it to approximately their height, the total mass of the planet would not increase because the potential energy gained by the hammers have been achieved due to the work done by people and the energy stored in their body have been utilised to do work , so it's a simple conversion of energy from one form to another . Moreover nothing has been added to the earth -person-hammer system , so there is no point of getting the mass changed of the planet.

In short , the mass of the planet would not change at all.