I was once asked at a University PPE interview, Does time have a colour? I found it both extremely interesting and baffling. My opinion was that as time was not a physical property it could not have a colour yet I questioned myself countless times. What's your opinion - could time have a colour? K(17)

I suspect the point of this question was to see whether you could articulate the idea of a "category error," that is a statement that is syntactically correct but is nonsense because its predicate cannot meaningfully be attributed to its subject. If this is what the interviewer had in mind, your answer was essentially correct but could have been stronger if you had explained that this was one example of a more general problem. If your interview was at an Oxford college, you probably would have earned bonus points if you had referred to Gilbert Ryle's classic discussion of category errors.