revenue expenses

HIIIIIII,

If we purchased 50 tube lights for our company it will be treated as capital expenditure.But if we replaced 10 out of them due to fuse then it will be treated as a capital exp. or revenue exp.?????

Because, according to the definition the exp. will be capitalised only when it will increased the productivity or reducing the cost of production.

plz helppppppppp

thnx in advance