It’s not a Mac-Hack (I assume that’s clear), but let me just explain the difference between a nuclear bomb and a dirty bomb.
A nuclear bomb uses a nuclear reaction to create energy. If you take some large mass element (let’s just say plutonium) and spit it into two pieces, you get some stuff. Obviously you get at least two smaller atoms. But you also get some neutrons and stuff. However, if you added up the mass of all the stuff after the split, it would be slightly less than the mass of the original plutonium. This lost mass is accounted for in energy. Here is the energy-mass relationship.
The “c” is the speed of light. This says that you get a BUNCH of energy for just a little bit of mass and this is the basis for a nuclear fission reaction. For a nuclear bomb, the split creates neutrons that can also split more atoms which produces MORE neutrons and more splits. Oh, the energy and the left over pieces tend to make stuff radioactive.
The dirty bomb also uses radioactive material. However, the main explosion is not a nuclear reaction but instead a more conventional chemical-based bomb. The bomb includes radioactive material that gets spread around from the explosion. It’s dirty. Yes, it’s bad—but it’s not a nuclear explosion. Also, these are pretty easy to make since you just need a normal bomb and some radioactive material.
Parsecs and Time and Distance
Everyone (except Jack) is correct. The parsec is a unit of distance. It has to do with parallax. Here is a simple experiment. Hold your thumb out in front of your face. Now close one eye and look at your thumb. Hopefully there is something in the background that you can line it up with. Now close that eye and open the other one. Notice that your thumb now lines up with something else in the background? That’s parallax.
Wait. You didn’t actually do the eye thumb thing. Really, you should do that.
OK, back to the parsec. The motion of your thumb with respect to the background depend on the distance from your thumb to your face as well as the distance between your two eyes. What if you increase the distance between your eyes? What if this distance is the size of the Earth’s orbit around the Sun? In that case the change in observation locations (on different sides of the Sun) can be used to measure the distance to nearby stars. If a star has an apparent angular shift of 1 second of a degree, that’s a parsec.
I don’t know what to call this stuff. MacGyver injects some liquid into Bozer’s knife wound and it sort of seals it up so it won’t bleed. It’s not so much of a hack, but it does appear to be real.
It would be sort of like that expanding foam you use to seal cracks around your house—except for blood.
Fertilizer grenades
What do fertilizer and explosives have in common? Nitrogen. It’s really interesting if you think about it. The air we breath has a BUNCH of nitrogen in it—79 percent. However, it’s not so simple to get. Once humans figured out how to get the nitrogen, they used it for fertilizer and explosives.
But yeah, you can make explosives from fertilizer—but don’t.
Liquid Oxygen
Yeah, this is bad stuff. Of course it’s cold, but more important is that it’s oxygen. If you want to burn stuff, you need oxygen. Liquid oxygen is WAY denser than gas oxygen. So, if you put this stuff on something you can get a lot of fire.
How do you make it look like you killed someone? Fake blood would help. MacGyver mixes up a batch using cocoa mix and some fruit punch.
Here is another recipe.
Fog Machine
MacGyver needs some smoke or something like that so he can elude the bad guys. In this case, he is going to use the water in the pool to make a giant humidifier.
OK, this isn’t smoke. It’s water vapor—water in a gas state. You can see through water vapor, because it’s in the air right now (hopefully). However, when the water vapor condenses out of the air, it makes tiny drops of water. These tiny drops of water reflect light to give a similar appearance to smoke.
But how do you make water vapor from a pool? One way is to use a spinning rod. If you put a rod that spins very fast in the water, some of the water will interact with the spinning rod. If the rod is spinning fast enough, then this water will get “flung” into the air.
Honestly, this a great physics joke. MacGyver and Jack are in a trash compactor—yes, there are some Star Wars jokes here too. In order to break the hydraulic pump, Mac wants to put a pole so that it pokes through a particular screw. Here’s the important part.
MacGyver: …if I hold the pipe perfectly normal.
Jack: Dude. Nothing about this is normal.
Jack messes up and hurts his arm. According to MacGyver: “I used a technical term that Jack didn’t understand.”
Ok, so what does “normal” mean? In short, it means perpendicular. That’s it. MacGyver needed the pipe to be perpendicular to the wall. That’s what normal means. That’s also why physicists call the force a surface pushes on an object “the normal force” —because it’s perpendicular to the surface.
Yes, we also use “normal” in geometry—but of course Jack wouldn’t get that.
What is a spectrometer?
Not a MacGyver hack, but I want to talk about spectrometers anyway.
My first idea of a spectrometer is a visible-light spectrometer. This is essentially a prism. Light goes into the prism and is then separated into different colors. By looking at the colors in the light you can identify the light source. Oh, but this kind of spectrometer wouldn’t be found in a chemistry lab—at least probably not.
There is also a mass spectrometer. This takes a gas of molecules and shoots them into an area. Using magnetic fields, the path of the molecules is bent. Based on the amount of particle deflection, you can get a value for the mass of the particles.
Also, it’s just fun to say “mass spectrometer”.
Origin of Hacking
Come on. We know that MIT didn’t really invent hacking. Humans have always been able to creatively figure out problems—which is the essence of hacking.
Another non-MacGyver hack. This is a hack from his friend. She creates a door alarm. You can’t really see it very well, but it would be a small battery with a buzzer. The circuit runs to a clothes pin with aluminum foil on the pinchers and a piece of paper between them. Since the paper is an insulator, there is not a closed circuit. The paper is then attached to the door (with tape) so that opening the door pulls the paper out.
It’s actually a pretty simple design. You can (and should) build one of these yourself. Here is a video showing how to do that.
Electric Whip
In order to make an improvised weapon, Mac takes an extension cord and cuts off one end. Then he strips the wires on that end and plugs it in to the wall outlet. Note: DON’T DO THIS.
When the two bare ends of the wires touch someone, they will get shocked. Oh, and it’s a whip.
So, would this work? I think it would mostly work. It wouldn’t make the lightning stuff, but that just makes it look cool. It does look cool, right?
DIY Centrifuge
This might be the best hack in MacGyver history. Basically, this is a real life MacGyver-hack. It’s a low cost and simple to build centrifuge.
What the heck is a centrifuge? It’s a super high speed spinning thingy. You can put liquids in there and the high rotation rate causes a centrifugal force (yes, I used that term correctly) to separate liquids of different densities. This can be used to process blood.
Here is a real centrifuge.
And here is the DIY version. It’s basically just string and cardboard. However, with this simple version people can process blood stuff in more rural areas. Awesome.
Hold on. There’s a metric butt ton of science in this episode. It’s going to be great.
Turning bullet
SPOILER ALERT. This episode has a bullet that can turn. It’s sort of the key plot element in this episode. These dudes are trying to steal the technology for these “smart bullets”. These bullets are essentially tiny guided missiles with fins so that they can turn in flight.
Again, not a hack—but MacGyver thinks birthdays are dumb. Well, not dumb but arbitrary. I think he is right. In fact, I use the following phrase on people’s birthday’s:
Happy Solar Orbit Day.
Yes, that is the day the person completes another orbit around the Sun. I like thinking of it that way.
Fixing a generator inverter
There are lots of different types of generators. Most of them involve a gasoline engine that turns stuff. Some times this turning stuff involves a magnet to make an electric current. But what happens when the magnet get’s messed up? Yes, you have to fix it.
A permanent magnet is a ferromagnetic object (like iron) in which all the magnetic domains are aligned. If the domains are not aligned then it would just act like a dumb piece of metal. You can get the domains align by applying a strong magnetic field.
This is exactly what MacGyver does to the generator. He uses a defibrillator to generate the current and forms a loop of wire to create the strong external magnetic field. Seems like it could work.
DIY sand blaster
How do you get people out of a collapsed building? What if you could just cut through the wall? Yes, that’s the MacGyver plan.
In this case, he uses high pressure water mixed with sand—a type of sand blaster. If you have water at a high enough pressure, it can pretty much cut through anything. Of course MacGyver’s water by itself isn’t fast enough. That’s where the sand comes in. When the sand hits the concrete, the abrasive interaction is enough to eat away at the concrete.
Oh, this would take quite a while to work.
Seeing through walls with radar
Yes, this is a real thing. NASA made this device. Here is a description. Basically, this thing sends out microwaves and detects the reflected microwaves. But the magic is that it only looks for variations in reflections caused by small oscillations—these oscillations are from a human heart.
For MacGyver’s version, he starts with a radar gun (from a police car). These don’t use the same frequency as the microwave detector, but he can make a modification. With some software from Riley, that’s pretty much what he needs to get started. It’s at least plausible.
Screw jack
How do you lift super heavy stuff? You need a simple machine. All of the simple machines deal with force and distance. If you can increase the distance over which you apply a force, you can get a greater output force over a shorter distance.
In this case, MacGyver makes a screw jack. You can lift a large mass by turning the screw to get it to extend. In fact, you could do something like this yourself. Here’s how.
Ascender rig
The goal of an ascender rig is to allow some device to move UP a rope, but not down. This means you can climb up a rope one little bit at a time. Here is an example.
Oh, MacGyver made an ascender rig to climb an elevator cable and escape a collapsed building.
Modify laser
The smart bullet is aimed using a laser. Of course the bullet is only a little bit smart. It only aims towards the brightest laser. If you could make another laser that gets the attention of the bullet, you can get the bullet off course.
MacGyver takes the laser sight off a pistol. In order to increase the power output, he burns off a potentiometer. This could work on some lasers—like this.
Oh, DON’T DO THIS. You don’t want a powerful laser without knowing what it can do. These lasers can seriously damage your eyes in ways you wouldn’t be able to predict. Remember, you only have two eyes. Don’t mess them up.
So, they use this powerful laser to redirect a smart bullet. That part is plausible. It’s unlikely they could get a bullet to turn all the way around. They wouldn’t have time to move the laser dot and the bullet fins couldn’t make it turn that much.
Again, this is not a MacGyver-hack. Well, I guess it sort of is a Mac-hack since he designed the LIDAR. So, what is LIDAR? At the most basic level, LIDAR uses a laser to determine the distance to an object. By scanning this laser over some area, you can get a very detailed distance map. If you know the location of the LIDAR (in the aircraft), you get a very nice map of the terrain below.
But how do you get distance with a laser? The laser produces a beam of light (that’s what the “L” stands for in “laser”) and this light travels at a speed of about . Yes, that is super fast. However, it’s not infinitely fast. So when this laser light travels and reflects off of something, it takes time to get back to the LIDAR. The longer it takes to return, the greater the distance. That’s the basic idea of LIDAR.
How do you start a jet engine?
I’m not an aeronautical engineer (in case you didn’t already figure that out). So here is my very simple explanation of a jet engine. The key to getting thrust is the same as a propeller driven aircraft: make the air coming in go faster as it leaves. This increase of air speed (into and out of the engine) means a change in momentum and thus a forward pushing force. For the jet engine, it increases the final speed of the outgoing air by also heating it by burning fuel.
So, how do you start a jet engine? It’s not the same as starting your car (but not completely different either). The main thing is that you need to get the jet turbines spinning first so that there is air moving through the engine. Then you can add the burning fuel to get the thing started. Here is a great video on how this works. Oh, this is why youtube is so nice—you can find a video on pretty much anything.
Pick lock with a paperclip
Oh, you missed this hack—didn’t you. When MacGyver gets into the old building, he has a paperclip in has hand. So, can you pick a lock with a paperclip? Maybe. You could use the paperclip to jiggle the lock pins, but you would need something to apply torque to the lock cylinder.
Here is a tutorial on lock picking—but don’t be a bad guy.
Break open door with a raft
MacGyver pushes open a locked door by filling a raft with water. Let’s start with the definition of pressure. Pressure is a force divided by an area.
Let’s start with the definition of pressure. Pressure is a force divided by an area.
You can solve this for the force.
So, if you have a pressure (in the raft) it will produce a force equal to the product of the pressure and the contact area. The bigger the area, the greater the force. In fact, with just a small pressure you can get a pretty big force.
OK, this is from a previous episode but I still like it. Here is a demonstration in which I use the pressure from my lungs to lift myself. Yes, small pressure with a large area means a significant e force.
What about the water? Well, the water will give the raft more mass so that it doesn’t just push itself away from the door. If you want to open the door with air pressure, you would need to have something hold the raft agains the door.
Dart gun
I love this visual effect where MacGyver is looking around for stuff to build and it shows all the things he sees. In the end, he builds a dart gun that shoots morphine needles.
Really, I just want to talk about two parts of this build—the shooting and the injecting. MacGyver uses a propane tank to shoot the dart. This is the same as your basic potato gun. Compressed gas from the tank push the dart in the tube. The longer the distance of the tube, the greater the final speed of the dart.
For the injection, you can’t just shoot a needle into someone. You need to push that plunger on the back of the needle to get the drug into a body. That’s where the steel spacers come into play. When the front of the dart hits a person, it will stop. However, the mass on the back will want to keep going until a force slows it down. This force comes from the plunger—that means the plunger gets depressed and the bad guys get drugged.
Beam splitter
How do you make one laser look like many lasers? You need a beam splitter. This is exactly what MacGyver does to fool the baddies into thinking there are bunch of other good guys in the woods.
Basically, a beam splitter is a piece of glass. We like to think of glass as being transparent so that light goes right through it—and it does. That’s why we use glass for windows to see stuff outside. But light also reflects off glass. In fact, if the light (from the laser) hits the glass at an angle then you will get both transmission AND reflection.
It doesn’t even need to be glass. Here is a quick demonstration of a beam splitter with just a piece of clear plastic.
Dog’s are pretty awesome for smelling stuff. They have noses that are much more sensitive than a human and they are smart enough to be trained. Oh, also they are dogs—so that’s an extra bonus. Dogs can detect more than guns. When trained, they can sniff out drugs or even some humans with particular medical conditions. Pretty awesome.
Again, not a MacGyver hack. Instead, there is a scene in which Desi (yes, Desi is the new recruit) runs and uses a corner of two walls to climb on top of a storage container.
So, how the heck do you run up a wall? The answer is “friction” and “momentum”. Let’s start with friction.
When two surfaces interact, there can be a frictional force. This force is parallel to the surfaces and proportional the perpendicular force that pushes the two surfaces together (we call this the normal force). If you put a book on a flat table, you can feel that frictional force as you try to slide the book. If you push DOWN on the book while trying to pull it, the frictional force will increase.
Since you have a vertical wall, it’s possible to have an upward frictional force to prevent Desi from falling down. However, there needs to be a force pushing Desi INTO the wall in order to have a significant perpendicular force. Actually, try this yourself. Take that same book you had on the table. Now put it on a vertical wall and let go. Yes. It falls. There is nothing pushing the book into the wall so there is no frictional force.
Now for momentum. Momentum (represented by “p”) is the product of an object’s (or human’s) mass and velocity where the velocity is a vector (depends on both the speed and the direction). Momentum is important in its relationship to the net force on an object. Here, we have the momentum principle:
So, what happens when Desi runs TOWARDS a wall and pushes off? The direction of her momentum changes from towards the wall to away from the wall. This change in momentum means there must be a force on her. Yes, this force comes from the wall. The faster she runs towards the wall, the greater her change in momentum and the larger the normal force.
This means a large normal force also produces a large frictional force. The frictional force is high enough to prevent Desi from falling while in contact with the wall. In fact, it’s a large enough force for her to move UP the wall. Of course, she is also now moving away from the wall. This is where the second wall comes into play. Now she just does the same this with that other corner wall. Physics.
Smoke screen
MacGyver needs a distraction. He takes some gun oil (used to trick the dog) and pours it into the engine of a forklift. When the fork lift starts, it is now running with extra oil in the fuel. This oil produces a blue-white smoke that comes out the exhaust. Yes, you have seen this with cars. It’s a bad sign that there is oil leaking into the engine cylinders.
The next thing that MacGyver does is to cut the fuel line. This pours extra diesel onto the hot engine. Theoretically, it could catch fire. Theoretically, this fire could cause an explosion. In theory.
DIY dog whistle
Yes, you can indeed make a whistle from a stick. Some sticks are easier than others—but still…
What makes a dog whistle different than a whistle? It’s really just the fundamental frequency that it blows. A normal whistle has a lower frequency that human ears are good at detecting. The dog whistle has a much higher frequency that most humans can’t hear.
Oh, what about the plastic bag? Yes, MacGyver gets a plastic bag and attaches this to the whistle. This makes an improvised bellows. The idea is that you can fill it up with air and then push the air out at a greater rate than just blowing. It makes the whistle louder than normal.
RFID detection
Cody (the dog) has an RFID chip in him. The basic idea behind a passive RFID is that you can excite it with a radio wave such that it transmits some data (like an ID). Oh, but you have to get pretty close for this to work. Here is a nice RFID tutorial.
Now for the MacGyver hack. In order to find Cody with his RFID, they need two things. First, they need a method to activate the passive RFID at a long range. To do this you need lots of power. That’s where the AM radio station comes in. If you use a nearby radio transmitter, it could activate a bunch of RFID tags. This is fairly plausible. No, you wouldn’t “hear” anything—it would just broadcast a particular frequency that the RFID uses.
The second thing—something to detect the RFID signal from a range. That’s why you need a satellite dish. The parabolic dish reflects weak radio signals into the detector. Of course this only works if you are pointing it in the right direction. So, you need to sweep this over some area until you get a signal. Once you find the dog you want, you have to use the dish to zero in on the location.
Disabling a car
What can you do to prevent a car from driving? Yes, there is the classic banana up a tail pipe trick (from Beverly Hills Cop), but how about something different?
OK, I admit this is a bit of a stretch. However, if you can make some sort of electromagnetic pulse device then it can interfere with the car’s electronic system.
That’s “essentially” what MacGyver does here. Let’s just leave it at that.
Foam fire extinguisher
How do you put out a fire? One way is to remove oxygen from the fire. Without oxygen, the fire can’t burn. This is essentially what a carbon dioxide fire extinguisher does. It shoots out carbon dioxide gas which displaces the oxygen and the fire goes out.
You can make a foam-based fire extinguisher that essentially does the same thing. The only difference is that the carbon dioxide is trapped in the foam. This means that you can cover some stuff with the foam and it should put out the fire.
Now for the fun part. You can make fire extinguishing foam with three things: vinegar, baking soda, liquid soap.
When you mix baking soda and vinegar, it produces carbon dioxide. If you add soap to the vinegar, then it also bubbles. This is not too difficult to try (but it can get messy).
Take a propane tank and bicycle tube. Cut the bike tire to make it a hose and connect it to the propane tank. Use a road flare to light the gas—boom. There is your flame thrower.
Oh but wait. It’s just a dream. Bozer’s dream. The flame thrower wasn’t real anyway.
Listen in on a landline phone
Who uses a landline now anyway? Oh well. They want to use a landline then it’s possible to listen in. Actually, this isn’t even that difficult. Check it out.
Here is another version.
You just need a capacitor and maybe an inductor. You could grab these from a radio or something like that.
But wait. I made a mistake. While going over this hack, I said something like this:
“Yeah, this is pretty easy. Just get the capacitor and earpiece (or radio) and then tie it into the wiring box”
Here’s what that looks like.
I just want to point out this small mistake (that you would never notice) just in case you saw it. You don’t actually “tie” the lines—that’s just a term we use in circuits to mean “connect”.
Bomb radius calculation
There’s a bomb in the truck. Where should you park it so that no one gets hurt? Yeah, this is a tough calculation. However, tough has never stopped MacGyver before and it won’t stop him now.
Here is my rough calculation and explaination.
Bombs are complicated. But usually it is the pressure produced by the explosion that will get you. We can come up with some pretty useful models to calculate their impact. First, there is the Hopkinson-Cranz Scaling Law (this is a real thing). With this law, the acceptable distance can be calculated based on the explosive weight.
In this expression z is a factor that depends on the type of distance with 14.8 being the distance factor for a public traffic route. That means that 2 kilograms would need 18.6 meters (60 feet).
Infrared face jammer
OK, it doesn’t actually jam your face. That would be weird. MacGyver wants to prevent the security cameras from recognizing their faces. So he takes some infrared TV removes and pulls out the IR LED lights. Normally these flash on and off so that the sensor on the TV can “see them” but humans can’t.
He mounts these IR LED lights on some sun glasses with a battery to power them. When a security camera sees the face, it just gets blinded by the IR light since many video cameras can also detect IR.
If your phone camera doesn’t have an IR filter (most now do) then you can actually see the light flashing on a TV remote by pointing it at your phone.
How do you open a locked car door? One way is to jam a wedge into the door. This will pull the door out just a little (by bending it) so that you can get a stick in there. The stick then can be used to push the “lock” button.
In this case, MacGyver uses something for the wedge—maybe a shoe horn or a door stop. Then a monopod is extended to click the lock button.
DIY soldering iron
You might have missed this one. But as MacGyver is building his stuff for the last mission, he needs a soldering iron. He takes the heating element out of a hair dryer and connects it to some stuff. That works.
Fake noses
Need a disguise? How about DIY latex to make a nose? Yes, this seems plausible. Here’s how to do it.
DIY keypad cracker
MacGyver makes a quick circuit board that can crack a keypad by using a brute force method that goes through all the combinations. This is from a different episode, but it’s the same idea.
If you want to play with one yourself, here is an online version of the code.
Well, it’s just a radio. MacGyver needs a speaker and a transmitter. Really, a radio transmitter is essentially the same thing as a radio receiver—OK, not really but sort of.
Instead of going over the way MacGyver did it, how about a real actual radio you could build yourself? Here is a spark gap transmitter from simple parts (and awesome).
Yes, it’s true. You don’t really sink all the way down in quicksand—that’s because the density of the stuff is greater than the density of water. Essentially, you float.
Here is a nice video on quicksand.
Pool shot.
I. Love. This. So, MacGyver is there trying to score a nice shot in pool (the game, not the pool). He starts thinking about all the physics to get the perfect shot—one with some curve. Here is what goes through his mind.
That’s pretty awesome, right? Let’s go over some of the key equations.
First, why does the ball turn? If you want to turn, you have to have a sideways force. In this case, the sideways force is a frictional force on the ball as it spins and slides on the table.
Once you know the frictional force, you can use this to find the new vector velocity after some short time. This is basically the numerical version of the definition of acceleration. Here’s that equation.
Oh, vectors. Look at the vector notation. Winning.
Next there is the changing angular speed of the ball. Since the ball is spinning with a frictional force, the ball would slow down. We describe the change in angular motion by using the angular momentum principle. This states:
Where L is the angular momentum vector. For a rigid object, the angular momentum is the product of the moment of inertia and the angular velocity (for most cases).
Where I is the moment of inertia (or as I like to call it, the rotational mass) for a sphere.
That’s pretty much all the equations you see.
Of course the amazing part is that humans can make these very complicated shots WITHOUT doing the calculations. I don’t know how that works.
Zip-tie nunchucks.
Two broken pieces of a pool stick and a towel. Boom. Nunchuck. But this is all I can think of.
Magnet phone tracker
How do you track a fleeing truck? You stick your smart phone on the bottom using a magnet. Oh, this works so well that Spider-Man used this same trick the following year in Spider-Man: Homecoming when he left his phone in the Vulture’s car.
There is a small problem with those car magnets. They are like refrigerator magnets in that they have weird magnetic domains. Actually, you should try this experiment.
Grab a fridge magnet.
Flip it around and put it on the fridge.
Oh, it doesn’t work!
The magnetic domains in these flat magnets are such that they stick on one side but not the other. That makes it tough to use for a magnetic phone tracker.
A better method would be to run a wire (or zip tie) through the magnet and around the phone. Like this.
Stab pepper spray with a knife
Yes, if you poke a hole in a can of pepper spray it will get pepper spray all over the place.
Circuit board knife
MacGyver uses a broken circuit board to cut through zip ties. Zip ties aren’t that strong anyway—it seems very plausible that you could sharpen a circuit board to cut through one of these things.
Control a car remotely
Is it possible to control a car with a computer? Sadly, this is real.
It’s too late to change now—but I wish I had planned better for my titles for these science notes. I just don’t like the way it looks. Oh well. On to the science.
Jumping out of window with a TV cable
MacGyver yanks a TV cable from the wall and ties it around him. Then boom—he’s out of the second story window to catch a bad guy. As he falls, the cable gets pulled from the wall and sort of prevents him from a full force impact with the ground.
The basic idea is to take a conducting sheet and lay it on top of the area where you want to find a print (finger print or shoe print). When a large electric field is applied, the dust literally gets lifted and stuck to the conducting sheet. Boom. There is your print. Oh, you need about 800 volts to get a high enough electric field (according to one paper that is no longer online for some reason).
For the MacGyver version, he uses some mylar for the sheet. In order to create the large electric field, he can use the charging capacitor for the flash in a disposable camera. That might not get up to 800 volts, but it’s a good start. Yes, it’s also true that you can get fairly high voltages just by rubbing two different materials together—as long as the air is dry. This is exactly what happens when you rub your feet across a carpeted floor and then shock the bejeezus out of someone. Same idea.
One more thing. The official version of the electrostatic dust print lifter is pretty expensive. But someone made one for just 50 dollars using a stun gun. Here is the hackaday.com link, but it looks like the original post has link rotted.
Just to show you some more electrostatic stuff—here are some demos that you could try.
Open an envelope with steam from a radiator
Yup, this works.
Wifi wall detector
OK, it doesn’t detect walls. Instead, the wifi can find empty spaces behind walls. MacGyver takes a wifi router with a partially parabolic dish (using aluminum foil) over the antenna. He then connects the output to a speaker (for a cool effect).
Yes, wifi is essentially a radio wave (it is a radio wave). Radio waves mostly pass through walls—but you have wifi in your house and you know that sometimes you don’t get a great signal. This shows that wifi is at least partially blocked by walls. The wifi can also reflect off stuff.
It is this reflected wifi that MacGyver uses to find the hidden room. When there is nothing on the back side of a wall, you don’t get a good reflected signal and that changes the sound of the connected speaker.
OK, this probably wouldn’t work—but it’s still based on this idea that wifi can interact with walls in different ways. Anyway, MIT has created a tool to use wifi to see through walls. Note, this show came out before that. I’m not saying MIT based that wifi thing on this episodes. I’m just sayin.
Movie film roll for distracting fire
MacGyver takes one of those movie film rolls. Adds some stuff and then lights it on fire. When he rolls it down to the front of the movie theater—boom. Distracting explosion. Yeah, lots of stuff burns. No problem here.
. Yes, that is super fast. However, it’s not infinitely fast. So when this laser light travels and reflects off of something, it takes time to get back to the LIDAR. The longer it takes to return, the greater the distance. That’s the basic idea of LIDAR.
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