2 bulbs have gone at the same time. Coincidence or a problem ?

[Dave7]

My hallway is quite long so has 2 ceiling lights. They have normal bayonet bulbs that have been in for years.
Last night they both just 'went'. They didnt explode, just stopped working.
All the other bulbs are OK.
I will nip out and get 2 new ones but it puzzles me that they both decide to go a the same time.
NB
One is led and you can see that the wire filament thingy is broken

 

[fossyant]

You can sometimes get a surge when bulbs go - we've has some trip our RCD !

 

[BrumJim]

Professionally, I refuse to get excited about 2 failures. Life is a lot less random than you think, i.e. if you toss a coin and note head or tails, you will get a number of consecutive heads (or tails) that will just seem unnatural. It isn't.

3 failures? Time to take an interest.

 

[Dave7]

You can sometimes get a surge when bulbs go - we've has some trip our RCD !

TBH i did think of that but why would that affect just those 2 when there are a leather 2 other lights on the same (do you call it) circuit?

 

[Dave7]

Professionally, I refuse to get excited about 2 failures. Life is a lot less random than you think, i.e. if you toss a coin and note head or tails, you will get a number of consecutive heads (or tails) that will just seem unnatural. It isn't.

3 failures? Time to take an interest.

Will soon find out as I've got the 2 new ones.
I will have to get someone to change them as my balance (or lack of it) won't allow me on a ladder.

 

[si_c]

TBH i did think of that but why would that affect just those 2 when there are a leather 2 other lights on the same (do you call it) circuit?

Age, particular quality of the batch the bulbs were made in, could be any of a number of reasons. Randomness is a whole lot less intuitive than you may realise, I could talk about this subject for a while (I'm a statistician) but I won't, you'll be bored.

If you want one example of why though, look up Benford's Law.