So, the question is as follows:
What is the difference in work exerted by the rider in the two following scenarios?
a) Rider + bike. Water carried in a holder on the frame
b) Rider + bike. Water carried in a backpack
(for simplicity, assumption that weight of holder = weight of backpack and backpack is perfectly aerodynamic, not increasing drag)
I would assume that in case a), as the weight is closer to the bike's centre of mass, it would require the least amount of extra work, compared to b), where the weight is more distant from the centre of mass.
Thanks in advance.