simple question?

On a form I want the choice input to one field (category) to automatically give an output in another field (location). That is, if someone inputs "cooking" in (category) I want to automatically show "kitchen" in (location). I have a number of categories all of which i want to link to different locations. Am new to using access and would appreciate any help, in simple terms if possible.
regards

Sorry, i just realised i hadnt fully explained my problem.
I am new to access and have modified a template database to keep a track of scientific papers. I have these papers in different categories, physics, chemistry etc. for each category there are papers i have on hard copy, others i have in electronic format and some that i have entered in the database but dont actually possess. I have a pull down box on my database where i can choose the category for a new entry, and I have 2 tick boxes one for hard copy and one for electronic format. Another location field is to say where my hard copies are stored. What i want the database to do is when i choose for example physics as the category for a new entry, I want the location field to automatically display the location, say "File 1" BUT only if i also tick the hardcopy box. If i dont have it on hard copy I will leave this box empty and tick the electronic format box instead, in which case the location field should also remain empty.
Any suggestions.? Please bear in mind I know little about writing code and find the access help somewhat complicated.