Home Alone: trap evaluation


May the wet bandits rest in peace, or pieces after Kevin is done with them.

Jacob Reiter, Staff Writer

When people think of Christmas movies, 1990’s Home Alone and its 1992 sequel Home Alone 2 are some of the first that come to mind. The part that I would assume most children (including myself) enjoy the most is near the end where the burglars Harry and Marv fall victim to Kevin’s numerous Rube-Goldberg-esque traps. From this point on the movie becomes mostly slapstick humor. A personal friend of mine, senior Cole Shenk (without whose help this article would not be possible), and I evaluated the physics behind the traps and by extension if they were lethal.


The first trap we evaluated was the scene where Marv pulls on what he believes to be a lightbulb chain, which prompts a clothing iron to fall on his head from the clothing chute above. We determined that the clothing iron was around three pounds and that it fell for roughly 4.17 seconds with a velocity of 41 meters per second. This would deliver an extraordinary 300,000 newtons into Marv’s face. It takes roughly 5000 newtons to completely shatter the human skull, meaning that Marv has died 60 times over from just this trap alone. From this point on we knew that the rest of the traps we were going to evaluate were going to be absolutely brutal.


The second trap we evaluated was when Harry repeatedly slipped on the stairs attempting to get to the front door and managed to fall onto the back of his neck on top of one of the stairs. Harry’s height is about 5’4″ and his weight is 120 pounds. It looks like he fell the entirety of his height onto the step, meaning that he would experience 72,000 newtons to the back of his neck. The spine can only take 3000 newtons before it is severed from the brain, killing the person instantly. From this scene, Harry has died 24 times over.


The third begins the trap sequence of Home Alone 2, Harry’s cap is lit on fire reminiscent of the first movie. His first instinct is to put the fire out by dipping his head in a nearby toilet; Kevin had thought of this, however, and filled it with gasoline. The camera then cuts to the outside of the building to show the explosion; watching this in slow motion we saw that the glass didn’t so much as shatter. This means that the force of the explosion would have to be below 1/100 psi before it got to the window. The room appeared to be 20ft by 20ft by 10ft. Since the explosion filled the entire room we concluded that the center of the explosion would experience roughly 20 psi, which is survivable for a human, although he would be knocked out cold.


Immediately after, Marv for some reason decides it would be a good idea to grab both the positive and negative ends of an AC/DC arc welder. From the shot before Marv gets electrocuted, we can see that Kevin turned up the welder to its maximum of an AC setting of 225 amps. The human heart can only take seven to eight milliamps before it stops functioning. Even at the lowest setting of 30 amps, Marv is dead thousands of times over.


We decided to send the article and these two poor unfortunate souls off together with what we call “the double kill.” Kevin attempts to swing paint cans down a stairway like he did in the first movie only for the burglars to anticipate it and dodge them. Unfortunately for them, Kevin anticipated their anticipation and prepared a segment of a sewage pipe to swing down and hit them both in the head. The force that the pipe would exert by impacting their heads would be split between the both of them, sending 5000 newtons each into their faces. The limit for shattering the skull is 5000 newtons as established earlier which is just enough to end them both easily.


If there is a single thing that we learned from doing all this math, it’s that Kevin McCalister is a 100% bonafide murderer, but it was all in self-defense so maybe he’ll be let off the hook. It is Christmas after all. Happy holidays to all.