Post:
You have three switches in one room and a single light bulb in another room. You are allowed to visit the room with the light bulb only once. How do you figure out which switch controls the bulb? Write your answer in the comments before looking at other answers.
Comment:
If this were an interview question, the correct response would be "Do you have any relevant questions for me? Because have a long list of things that more deserving of my precious time than to think about this!
- Use the heat of the bulb to determine if it was on. (Shows you can memorize stupid interview questions)
- Ask a team member to coordinate with you in the other room. (You’re a team player)
- Use a cable locator (Proper tool for the trade)
- Put your phone in the other room, stream camera feed to your work laptop (The tech approach)
- Unscrew the bulb. Now you know that no switch controls the bulb (Exposing the flaw in the task’s phrasing)
- Open switch panel and disconnect one switch. Wait a day. If no one complains, disconnect the second. Wait a day. If no one complains, it’s probably the third. For good measure, disconnect the third switch. If still no one complains, remove all switches and the lightbulb, since they’re not needed anymore. (The Sysadmin approach)
I am the sysadmin and I approve this message.
It’s funny to read the reactions and the people not understanding that programming questions are not enough to judge you. We need people with functioning brains and that usually means problem solving skills. And sometimes the problems are fucking idiotic! Nobody cares about the light switches. We want to see how you think. We want people who don’t give up if they can’t look it up.
You think you’re hot shit because you learnt the latest trendy language? I’ve wasted entire days with people like that because they couldn’t be fucking arsed reading error messages and figuring things out by themselves.
Replace the Lightbulb with a paperclip then flip the switches until you hear the circuitbreaker trip
Dead serious question: I have only ever worked in the public sector (state level and local municipality) but often see or hear about these seemingly idiotic “interview questions” on television (and obviously memes).
Is this:
- just a meme
- just a joke
- an actual phenomenon in the private sector
If 3, what on earth is its purpose and what could the interviewer possibly find out about the applicant by asking this?
I’m calm.
In the private sector, I once was asked to come up with 12 uses for a kettle. I said make 12 cups of coffee. I didn’t get the job.
In the end it all boils down to heating water
That’s why you don’t make a 10 figure salary. It can also be used to boil oil to throw on invaders when the office is under siege
I think I was asked this very question in an interview once. I think I answered something along the lines of ‘If you have a light switch like that here in the office, the first thing I would recommend is calling in an electrician to change and move the switch to the correct room. Why would you have a light switch that controls a light in a different room and apparently two switches that do nothing??’
Got the job.
The bathroom where the switch is prone to get splashed?
Sure, but I would still argue the bathroom light switch should be located, I don’t know, next to the bathroom door? And most definitely there shouldn’t be two totally useless switches there.
I don’t think I would like to work for a company that struggles this much with light switches…
maybe dont care. hit all 3 of em. answer is: i have figured out that one of the 3 switches controls the bulb (or not)
You have to report back which individual switch it is such that another person is able to control the light bulb reliably because they know which switch
But they are able to control the lightbulb by flipping all three switches.
