I agree with JRandomFreeper.
But I think there are more factors.
Time(not redundant, as one might think), distance, gravity, and heat.
Add to that, attitude, drugs, memory ability, environment, (including other people).
I assure you, FIVE MINUTES when you are busy, busy, busy, is nothing like FIVE MINUTES sitting absolutely still, watching the clock count it off.
: )
Time can be very relative, especially if you have your relatives visiting for the weekend.
/johnny