Question regarding water potential

[nemzy]

today in bio lab we measured the change in weight of potatoes when it was placed in diff molal sucrose conc for 1 hour.

However, there was a question on the lab that i didnt understand

what condition must be met for the size and shape of potato pieces to have no influence upon the results of this effort to measure water potential for this tissue? (think about the required amt of incubation time)

wat the heck does the size and shape have anything to do with potato pieces having no influnece on water potential?

 

[BillTre]

what condition must be met for the size and shape of potato pieces to have no influence upon the results of this effort to measure water potential for this tissue? (think about the required amt of incubation time)

They are probably referring to how much mass of potato the change of weight is being measured in (more potato could such up or lose more water)
and in particular with respect to the amount of incubation time, the amount of surface area of potato exposed to the surrounding solution will be where any exchange of fluids occurs between the potato and the incubation solution. A small surface area will exchange materials more slowly than a large surface area. If left for an infinitely long time, any differences in surface area would not matter (because everything would approach equilibrium), but in a limited time frame, a slower rate of exchange could result in a reduced amount of potato weight change.