Transfer of Kinetic Energy Through House Walls?

[netrista]

Hello. I'm looking for a purely physical explanation for an unusual event that occurred in my home. The circumstances are humorous and creepy and cause for speculation concerning the paranormal. However, I believe we have identified the true cause of the phenomenon and want to vet it against scientific principles. Thus, I'm posting here to see if anyone can help affirm our hypothesis.

Essentially, a small child ran into the home, stopped and proclaimed there was a ghost in our house. I told her there were no ghosts. Right as I said that, we heard a loud sound my husband likened to a car striking the house. (I myself suspected a large, wooden bookcase had fallen over.) Then, a framed photograph flew nine feet across the room and landed on the floor.

It's trajectory meant it flew at a sharp diagonal, which no one would expect. Pictures have fallen off the wall before but have always dropped straight down to the floor. This occurred in the living room. Roughly four hours later, a wooden curtain rod crashed to the floor. This rod was hung in a room directly behind the living room. The rod ran parallel (just inches away) to the wall holding the flying picture, and its ends attached to two walls perpendicular to the wall holding the picture.

As a result, we suspect that tension in the rod was building up for some time due to the weight of clothing it held. Further, we suspect this tension transferred through the wall and provided the energy needed to slingshot the picture across the room. Is this a viable proposition? Please let us know.

While we are leaning to the rod tension theory, we are uncertain as to why such a loud noise precipitated the picture flying and why a similar phenomenon didn't obtain when the rod fell multiple times in the past.We also wonder why another picture of identical weight and size hung on the wall--by nothing more than a thumb tack, and only an inch or so away--was unaffected.

 

[Stephen Tashi]

Essentially, a small child ran into the home, stopped and proclaimed there was a ghost in our house.

Was this a small child that you knew?

 

[netrista]

Was this a small child that you knew?

Yes. This was a nine year old girl who had come to visit my son. She has been in the house many times before and had never said anything of the kind.

 

[netrista]

Attached, I am supplying a picture of that maps the trajectory taken by the picture. Unfortunately, I believe it will upload in the wrong orientation, which I do not believe I can correct. Additionally, pay no mind to our unusual decor. I say that, as some may interpret the child's statement to be based on the unusual items in our home. However, the child has been coming to the house for 2 years and barely notices the quirky and somewhat creepy items we've accumulated.

 

[Stephen Tashi]

Ask the child for details about what she saw. Perhaps you had an non-ghostly intruder in your house. Are any of your friends practical jokers?

Right as I said that, we heard a loud sound my husband likened to a car striking the house. (I myself suspected a large, wooden bookcase had fallen over.)

Is the noise still a mystery? How are the walls of the house constructed? Drywall over 2x4 studs? Something could have snapped inside a stud wall if it has a major structural problem.

 

[Borek]

Not clear to me what is the geometry of the rod, wall, room and everything, but in general I see no problem with the idea these things are related to the picture flying of the wall (I mean: I can think of a valid physics behind). Sure, it doesn't sound like something that happens every day. In a way - lucky you, I would love to see it by myself

 

[netrista]

Thank you for your reply, Borek! Out of curiosity, what sort of geometrical information would be needed to prove our theory? My husband and I are highly technical and would have no issue gathering up sufficient information. This is just a problem we've never had to solve before. While the ghost idea is quaint, we are new home owners and are more concerned with structural phenomena that may need to be addressed in the house and a simple closet rod issue would put our minds at ease.

 

[netrista]

Ask the child for details about what she saw. Perhaps you had an non-ghostly intruder in your house. Are any of your friends practical jokers?
Is the noise still a mystery? How are the walls of the house constructed? Drywall over 2x4 studs? Something could have snapped inside a stud wall if it has a major structural problem.

You've got my attention, Stephen! A broken stud wall sounds a lot scarier than ghosts. Anyway, this is a 1972 mobile home. The easiest way to explain it is to start with the room containing the clothing rod. It has a real, 8LX7H wall covered with mobile home panelling. Then, there's a 3X7 in gap between it and the back wall of the kitchen. This sizable gap was supposed to be a passage way to the living room. However, the owner took a bunch of panelling to create a closet that's 2 feet deep. The flying picture was attached to one piece of this paneling on the living room side. On the living room side, the owner used a mix of wood framing and panelling to create another recessed area by building out into the space. So, this whole area is composed of add-on elements.

Now the curtain rod was a solid piece of wood, one inch around. It was attached to the added-on closet space wall and the back of the kitchen wall. It had about 50 pieces of clothing on it including heavy outerwear. All this stuff was parallel to and inches behind the cheap panelling holding the picture. I can't get my scale to weight the clothes. I know I can barely lift 50lbs, and I suspect that the weight of the clothing was in this range, as I tried to pick them all up at once. The flying picture weighs roughly 3 lbs.

Finally, I can tell the screws are still firmly embedded in the walls. I've been knocking on the walls, feeling the walls and eyeballing the walls. Nothing looks or feels abnormal. The ceiling and walls look fine, as well. Considering how paper thin they are, I'm hoping this is a good sign. However, if there's any other way to identify stud issues without tearing the house apart, let me know. I'm attaching more annotated pictures for reference. Also, if it was a stuck, could the energy transfer into the paneling that wouldn't be near them?

Lastly, I had the occasion to question the child about the alleged ghost. She admitted the sound of central air being forced through creaky vents had spooked her.

 

[netrista]

Ask the child for details about what she saw. Perhaps you had an non-ghostly intruder in your house. Are any of your friends practical jokers?
Is the noise still a mystery? How are the walls of the house constructed? Drywall over 2x4 studs? Something could have snapped inside a stud wall if it has a major structural problem.

Stephen -- I raced to test your stud theory further, as this was alarming. From my perspective, the force likely struck the picture on its left edge and propelled it to the right. Therefore, I went into the closet and unscrewed the portion of the clothing rod still screwed to the wall. Then, I stuck a pin through the two screw holes. Surprisingly, there's no stud there. Another screw down a foot and over a foot from that one does not connect with anything either. Barring complete and sudden disintegration, there was never anything there. The weight of the rod was maintained solely by the cheap paneling. For the sake of completeness, I repeated the procedure on the opposite side. There is wood there. However, the screw was to short to even connect with the wood. The paneling was supporting that, too. I considered the possibility that something broke up above the ceiling panels. However, I'd hope that if cheap paneling could hold the weight of the clothes without splitting, wood in the ceiling could manage. Thus far, it appears that the plastic end attached to the wooden rod simply slipped off the screw head somehow. Consequently, it's conceivable that the flying picture/noise and the rod failure aren't related. That aside, it would seem to me that the impacting force would have had to have traveled straight through the paneling itself to get the correct, diagonal trajectory. The engineer in me wants to solve this, but there's nothing that I can ascertain that could propel force in that direction. Even if I was to run full bore into that panelling (at 160lbs), I tend to doubt that I could throw the picture clear across the room. This is a very frustrating mystery.

 

[Zach S]

Hello, I found some interest in this and decided to try and find a mathematical solution.

First using the range and an estimate of the angle I roughly calculated what the initial velocity would have been, then taking that and finding the mass of the picture frame which I see as quite accurate as I'm guessing the frame weighs about 1.5-2 pounds, now I found that the kinetic energy of the frame was about 4.57 Joules. Now the most odd thing is that behind the frame is a closet and I'm presuming that's not where the force came from.

Also the initial force that would caused the frame to fly would have been turned into other forms of energy as well like heat also would have been spread throughout the house weakening further away from where ever the original force came from. To me this seems incredibly odd it may help if you can identify where the original force happened, as it would have had to have been pretty big to transfer 4.57 joules into the frame being how ever far from the original force.

 

[zoobyshoe]

Here's an idea, for what it's worth:

Since the walls in question aren't rigidly supported, as per post #9, it is plausible that air could be sucked out from between the walls, causing them to bow inward. If the vacuum were then somehow suddenly broken, they might both pop back out quite quickly. The picture, being somehow strategically placed, was launched as it was, and the rod on the other side failed later, but from the same cause. The venting system that sounds like a ghost is the most likely suspect for what sucked the air out.

 

[Evo]

Sorry, the OP PM'd me earlier and said she had figured out what happened so ok to close the thread out.