what is the mass of 4.2 kg of gold when it is transferred to a planet having twice the
gravity of earth?

The only relationship is that the larger the mass of an object the more gravitational force it has. So... something that has more mass has more gravity. The mass of 4.2kg of gold when transferred to this new planet is still 4.2kg. However, the WEIGHT (not mass) is now doubled to 8.4kg. Mass is constant it is how much matter something is made up of. Weight depends on the gravitational force.

Explanation:

mechanics (greek   is that area of science concerned with the behaviour of physical bodies when subjected to forces or displacements, and the subsequent effects of the bodies on their environment. the scientific discipline has its origins in ancient greece with the writings of aristotle and archimedes[1][2][3] (see history of classical mechanics and timeline of classical mechanics). during the early modern period, scientists such as galileo, kepler, and newton laid the foundation for what is now known as classical mechanics. it is a branch of classical physics that deals with particles that are either at rest or are moving with velocities significantly less than the speed of light. it can also be defined as a branch of science which deals with the motion of and forces on objects. the field is yet less widely understood in terms of quantum theory.

explanation:

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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