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rolling



I need some help with the following question from Halliday et al (6th ed.),
ch. 12 question 5:

"A woman rolls a cylindrical drum, by means of a board on top, through the
distance L/2, which is half the board's length. The drum rolls smoothly, and
the board does not slide over the drum.
a) What length of board has rolled over the top of the drum?
b) How far has the woman walked?"

The answers in the book are L and 1.5 L. I am not sure I understand what is
meant by "what length of board has rolled over the top of the drum." It seems
to me that it should be L/2. If the questions means how far has the board
moved with respect to the ground then I agree it is L.

Answers in algebraic form (plus verbal explanations) are preferable to
strictly verbal arguments.

Justin