Science Buddies: "Ask an Expert"

So I am a Yr10 student and on the top classes so I need a rather difficult science experiment to gain full marks... Although it may be too easy, I was thinking of finding whether the storage temperature of an onion affects its ability to provoke human tears. I was just wondering if you would be able to aid me in finding out how exactly to measure human tears, rather than the reaction. If not, is there any other variations of this experiment you think would suit me ??

Dear christinaa3,
One way I think you can measure tears is by using an absorbent cotton pad which could be square or round and then measure the area of wetness on the pad. This should be pretty standardised as you will use pads of the same thickness and material throughout your experiment. I hope this helpful.
Jay