Skip to main content

When the Doorbell Rings @ 4 AM......

8th July 2007

Initially, I thought to put this post this on another blog but later I thought that it had something to with Physics and decided to put it here.

At around 4 AM in the night amidst heavy rains if the doorbell rings then one can get suspicious at first. And if after checking one finds that there is no one at the door then it may be a feeling of relief with curiosity. I had this experience and since I was aware of such incident (doorbell ringing on its own), I was keen to investigate what could have caused this in my case. My doorbell was not wireless which could be triggered by the switch of my neighbour (if coincidentally both doorbells worked at same frequency). The bell I use is a musical bell connected to the switch via wires.

The bell under consideration plays music only once at the time of pressing the switch. If one continues to press the switch it won't keep on playing music. On the day the doorbell played music at 4 AM, it did not do so later even if someone pressed the switch. However, when the mains power was switched off and switched on again, the doorbell did play music. Now, it looked as if at 4 AM something caused the two wires in the switch to come in electrical contact. When it happened first (i.e. at 4 AM on that day), there was music. Subsequently, since the wires remained in electrical contact, pressing the switch was irrelevant and doing so did not cause it to play music. When the mains was switched off, now even though those two wires remained in electrical contact, there was disconnection in the circuit and it played music when the mains was switched on.

While all these experiments confirm the theory that at 4 AM on that particular day, the two wires did come into contact, one can still wonder what could have caused them to come in contact. Was it wind? But then inside the switch where two wires are there, the effect of wind should be subdued. Since switch is outside, it could be the rain causing the two points to come in electrical contact (it doesn't necessarily have to be a physical contact). The water can find its way through a switch which is not water tight.

5th May 2008

I have been thinking about updating this post since a past few months. The bell rang later after rainy season when there were no rains. I tried to see inside the switch to investigate what could be responsible for the electrical contact and I could find a wasp there.


PS: Please refer to http://blog.123iitjee.com/2012/08/when-doorbell-rings-2-am.html as well.

Popular posts from this blog