Came up with a problem that I can't solve

[mfb]

The friction would not be the same as the weight of gold increases friction in contact with sloping surface.

Friction is also proportional to mass. If we neglect air resistance, all forces and energies are proportional to mass, and acceleration is independent of it. A simple dimensional analysis shows the same.

 

[golfrmyx]

mfb, I see my comment was not clear for some reason. The gold friction on the sloping surface would be more than that of glass that is more than plastic. The increased friction I was referring to would be the air resistance that is too large to ignore. I do not mean increased. Not sure why I used that word. The marbles I was mentioning must be the same diameter so mass would be the same and thus air friction the same. Gravitational pull is the major force.