This is the largest clock in the world,_ the minute hand is 6 meteres long.why using of which?

the subject of first half sentence 'This is the largest clock in the world’ is 'clock',while the subject of the other half is 'the minute hand',it is a part of the clock.Therefore,in the sentence it ...Thanks for you reply.Why "where=on/in the clock" can't be used here? In attributive clause, "where" denotes a place, an activity and a range.I know the minute hand is part of the clock. To some degree, it is a best answer.