Physics question

[OldFogey]

Assuming both have equal energy inputs, the heavier ball would have to stop first. More energy required to move more mass. Assuming this is not in zero g space environment.

[JohnnyEgo]

I should clarify that the weight component of friction will mean that the heavier ball experiences more rolling resistance, but the magnitude of this difference will most likely be relatively minor in comparison to the momentum disparity between the two balls. One could do the math on this, but I can't before I have to get my kid to camp.

[mb504]

I should clarify that the weight component of friction will mean that the heavier ball experiences more rolling resistance, but the magnitude of this difference will most likely be relatively minor in comparison to the momentum disparity between the two balls. One could do the math on this, but I can't before I have to get my kid to camp.

But he didn't want to use gravity in the original problem, rolling resistance requires gravity to hold the two surfaces together.

[JohnnyEgo]

But he didn't want to use gravity in the original problem, rolling resistance requires gravity to hold the two surfaces together.

Guess you missed the first part of my prior post. If no external forces are applied to the balls, they continue to roll along at 20mph in perpetuity.
But Ray was really asking about the impact of weight (mass, really) on momentum for two otherwise equal objects. He just didn't use those words. The second part of my prior post answered that question.
The follow-up comment was for those who would argue about oversimplification of the model. It wasn't meant as a stand-alone post.

More to the point of what Ray was getting at, if you have two identical Kia Sephias travelling at 20 miles per hour, with one filled with feathers and the other with a equal volume of lead, and both drivers hit the brakes at the same time, the heavier one is going to take more energy to stop (rolls longer).

[00tec]

Guess you missed the first part of my prior post. If no external forces are applied to the balls, they continue to roll along at 20mph in perpetuity.
But Ray was really asking about the impact of weight (mass, really) on momentum for two otherwise equal objects. He just didn't use those words. The second part of my prior post answered that question.
The follow-up comment was for those who would argue about oversimplification of the model. It wasn't meant as a stand-alone post.

More to the point of what Ray was getting at, if you have two identical Kia Sephias travelling at 20 miles per hour, with one filled with feathers and the other with a equal volume of lead, and both drivers hit the brakes at the same time, the heavier one is going to take more energy to stop (rolls longer).

Which leads us to the next question: Which is heavier, an ounce of gold, or an ounce of feathers?