Hello,

Though the questions that I post in this Homework help section are actually not related to my homework but appear in my 9th STD physics text book with the label "Think It Over", I feel it is appropriate to post them here, because even after much thinking I have not been able to find right explanation.

The question- "Is work done when rolling a marble on a frictionless plate?"

Thanks.

Edited December 26, 201015 yr by Akash Kagi

If we were to change the question a bit, we can separate three factors that underly the question. Then we can return to the original question.

 

"Is work done when a rolling marble crosses a frictionless plate in a vacuum?"

 

For this question one only considers work that might transfer from the marble to the surrounding. Can there be any?

 

What about when it is not in a vacuum? What about if one must push the marble to get it rolling?

 

Finally, what do you think was the intent of the question being asked in context with these questions I asked you to consider?

Well think about it this way, what is required for the marble to go from a stationary position to a moving one?

 

If we were to change the question a bit, we can separate three factors that underly the question. Then we can return to the original question.

"Is work done when a rolling marble crosses a frictionless plate in a vacuum?"

 

For this question one only considers work that might transfer from the marble to the surrounding. Can there be any?

 

What about when it is not in a vacuum? What about if one must push the marble to get it rolling?

 

Finally, what do you think was the intent of the question being asked in context with these questions I asked you to consider?

 

 

Well seeing as how this is from a year 9 physics text book and syntacticly the questions asks

 

Is work done when rolling a marble on a frictionless plate?

 

You can logically take it to mean that the verb rolling in this context is meaning a person somehow rolls the marble on a frictionless plate.

Edited December 26, 201015 yr by Nexium Tao