MacGyver Season 1 Episode 17 Science Notes: Ruler

Propane tank flame thrower

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.

\mathrm{Range} = (z)(\mathrm{weight})^(1/3)

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.

Oh, so this could really work. It just depends on the type of video cameras. Some people even put stuff like this on their car license plate so that police cameras can’t see them.

Car jacking

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.

Oh, here is the code on

DIY police radio

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).

Here is a more detailed explanation of the spark gap transmitter from one of my WIRED posts.

MacGyver Season 1 Episode 15 Science Notes: Magnifying Glass

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.

Electrostatic dust print lifter

Electrostatic dust print lifters are indeed real. Here is an example of a real one.

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 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.

MacGyver Season 3 Episode 14 Science Notes: Father + Bride + Betrayal

Hotel door break in with a coat hanger

MacGyver uses a series of coat hanger wires to build a device that opens a hotel door from the inside. It’s basically a long wire that goes under the door and pulls down on the handle from the inside. Here is a video of what that looks like.

Don’t break into other people’s hotel rooms. That’s illegal. You have been warned.

Oh, but that’s not the best part. MacGyver says this is really about torque. Yes, that’s true. You need to exert a torque on that inside handle to get it to turn.

Wait. The real best part is when Riley says “It means physics is awesome”. Yeah it does.

Thermite toothpaste

So the bad dude that is turning himself in has a special safe. If you try to break in—thermite melts the stuff inside. Yes. Thermite is real and thermite is awesome. In fact, here is an older video where we set off some thermite as a chemistry demo.

We need to do this again.

OK, but could you make thermite into a paste? You might be thinking “oh, if you put the thermite in toothpaste, it won’t get as much oxygen for the reaction.” Good idea—but surprise! Thermite has its own supply of oxygen. You can even get a thermite reaction to work underwater.

Really, the only issue with toothpaste is that you don’t want to get the thermite stuff (particles) too far apart so that they can still interact with nearby particles.

Spray can flame thrower with a bonus

Yes, we pretty much all know that if you get a spray can and shoot it into fire you get a mini flame thrower. Oh, I’ve never done this myself but I know a friend of a friend that did it that one time. I’m sure you’ve never tired this either.

But what about the bonus? If you get any type of fine powder, it also explodes (that’s the powdered sugar part that adds to the flame thrower). Yes, when particles are very small and very spread out—they can explode.

Here is an example from season 1.

Cyanide detection

It turns out that there is a fast method to test for cyanide poisoning (which can happen from certain fires—not just for spies).

Here is an article on how this works—

The basic idea is to get the cyanide the cyanide by mixing the blood with both an acid (muriatic acid and/or vinegar) and a base (like baking soda). Add this to a fluorescent agent like a detergent and then look at it with an ultraviolet light. If it glows—it’s cyanide. At least this is plausible.

Cyanide antidote

For the antidote, MacGyver is basically going to make sulfanegen—an experimental cyanide antidote. Yes, humans do indeed build up a sort of tolerance to cyanide since it’s a natural element in many fruits and stuff. Here is my half-plausible method.

  • You need sulfur. You can get this from match heads. Yes, that’s true.
  • Acid—cleaning supplies.
  • Hydrogen peroxide
  • Blood. Yes—that might be gross, but you do need that.
  • Heat it up and filter it with a coffee filter.

Now, how do you get it to Riley? You could use an IV—but a nasal spray should work too. This is why they give some kids the flu vaccine with a nasal spray.

Don’t actually try to cure someone with this recipe.

Finding the real bad person with interference

MacGyver uses the interference sound from Riley’s radio when she is attacked to figure out that someone is the bad person. Basically, someone had a device that interfered with the radio.

If you had a mobile phone (we didn’t call them smart phones because they weren’t that smart back then) in 90s or early 2000s, then you know what happens when they get near a speaker.

It’s entirely plausible that a medical alert bracelet could do this. In fact, medical equipment often uses older technology because they don’t like to move to newer stuff until it’s been fully tested.

In fact, there could be some type of extra interference caused by the taser and the medical bracelet. That’s what MacGyver wants to reproduce and detect. All he needs to do is to reproduce the taser signal and create an audio output so that he can “test” different people and find the baddie.

MacGyver Season 1 Episode 13 Science Notes: Large Blade

Tarp restraint

This is sort of like a straight jacket made out of a tarp and a belt. I wonder how long this would last—but it’s still a classic MacGyver hack. This blog would probably be better if I included pictures. Oh well.

Space blanket as chaff

A space blanket is basically a thin mylar sheet. It has a nice property in that it reflects infrared radiation. The idea is that you cover yourself with this and when your body radiates infrared light, it reflects it back to your body.

Can you use this as a countermeasure against a ground to air missile? Maybe. Of course there are two types of missiles. There is the heat seeking missile and the radar missile. For the heat seeking missile, it is guiding by the giant infrared source—the engine of the aircraft. It’s a least plausible that this space blanket could block the infrared light from the helicopter enough to confuse the missile. Possible.

If the missile is radar guided, then you can block the radar that comes out of the missile. This is the idea behind chaff (a real thing). It’s basically thin strips of metal that fall in the air behind an aircraft. The metal spreads out and can make a large radar reflection such that the missile thinks it’s a target.

Would a space blanket work? It’s possible. Really, you want metal—but this might work at least a little bit.

Splint and crutch from helicopter parts

Classic MacGyver stuff here. Nothing else to say.

Clean water from a tree

Can you get clean water from a tree? It seems like this is legitimate.

Dried wood as a desiccator 

This seems like a plausible way to dry out a wet phone. It would take some time though.

Swiss Army Knife as a signal mirror

MacGyver uses the blade on his knife to attempt to reflect sunlight towards a rescue helicopter. I’m pretty sure this would work.

As a side note—I’ve been thinking about the brightness of light reflected from a mirror (for another project). It seems like this is fairly difficult to calculate. Perhaps the best way is to just experimentally measure the brightness of reflected light. I guess I will do that at some point.

Tree sap and a battery to start a fire

If you want to use a battery to start a fire, you need an electrical conductor. This allows electric current to flow from one terminal of the battery to the other. It’s this electrical current that can make things get hot—hot enough to catch on fire.

So, the battery part is good. What about the tree sap? Yes—apparently, it is indeed a conductor. There you go, a fire.

Distance to lightning strikes

This is another reminder. I should write a post about how to estimate the distance to a storm. The short answer is that when lightning strikes it produces both light and sound. The light has a super high speed, but the sound is just fast (not super high fast). This means that the light gets to the observer first. By counting the time between the “flash” and the “boom” you can estimate the distance.

I thought I had already blogged about this—but I can’t find any such post.

Creating a homemade capacitor to store charge

Here is the short version: MacGyver makes a DIY electrical capacitor (a Leyden jar) to get some electrical charge from a lightning storm. He then uses this to power the satellite phone.

The Leyden jar is totally real. Honestly, I was surprised at how well this worked. Check it out.

Photo Google Photos

Also, I have a much longer blog post over at WIRED.

Finally, you can make something like this yourself.

Zipper as an wire

MacGyver uses the zipper to make a complete circuit from the battery to the sat phone. Would this work? It’s tough to say. In order to get an electric current, you need a closed circuit with a conductor the around the whole path.

Parts of a zipper are clearly conductors (the metal parts). However, if there are gaps between the metal, then it wouldn’t work. If you zip the zipper, there should be contact—at the very least, this is plausible.

MacGyver Season 1 Episode 10 Science Notes: Pliers

Boosting car speed.

Mac and Jack are trying to get away in a car chase (using a not very fast car). Of course MacGyver is going to give them a speed boost, but the first step is to remove the car hood. MacGyver makes some small explosives using chemicals and soda cans. Boom. No more hood.

The second step is to remove the air filter and pour some hydrogen peroxide into the intake. What would this do? This would give the gasoline more oxygen (from the hydrogen peroxide) to produce more combustion. Would this give a speed boost? Probably—at least a little bit.

Chemistry demo – elephant toothpaste.

This is real. Everyone does this—at least all the cool kids do it. You should be cool.

Liquid nitrogen in water

OK, liquid nitrogen is pretty awesome. It’s the same nitrogen that you find in the air, but in liquid form. That makes it very very cold (-196 C). When you add it to room temperature water, the liquid nitrogen boils. In this boiling process it produces a bunch of water vapor—stuff that looks like a cloud.

This was for a different episode, but here is my introduction to liquid nitrogen.

Remote listening device

MacGyver wants to hear what is going on inside a house. The obvious solution is to build a remote listening device. Here’s how it works.

A laser is aimed at a window such that the laser reflects off the window and back to a solar cell. Because people are inside the house speaking, this causes tiny vibrations in the window. The window vibrations vary the intensity of the reflected laser light. When this reflected laser light hits the solar cell, it causes variations in the voltage. Plugging this solar cell into an amplified speaker produces sound. Yes. This is real.

It’s pretty awesome—and you can do something like this yourself. All you need is an amplified speaker and a solar cell (don’t worry about the laser). Connect the solar cell to the audio input and you can hear variations in different light sources.

My favorite trick is to aim a TV remote at the solar cell. You can hear the variations in the IR light that produce different signals to change channels.

Here is a video.

Stop a car with paper

Yup, a version of the banana up the tail pipe from Beverly Hills Cop (great movie). See—everyone is a version of MacGyver at some point.

In this case, MacGyver sticks some paper up the tail pipe of a car. When the exhaust can’t escape, you can’t get internal combustion. Car stops.

Yaghi Antenna

Yes, you can build an antenna out of just about anything—including band instruments. It helps if they conduct electricity. I think this would work.

Technically it’s possible to find the location of a signal with just one antenna (well at least the direction). Just turn the antenna until you get the maximum signal. A better option is to use 2 or more antennas—but you have to work with what you have.

Over inflate tire

Yup. Boom.

Elephant toothpaste version 2

Bigger is better, right? It’s sort of funny.

MacGyver Season 3 Episode 13 Science Notes: Wilderness + Training + Survival

There is no funny intro for this post. Oh wait, this is an intro.

Rock and steel to make a spark.

OK, this isn’t actually a MacGyver hack in this episode but I’ve talked about it before. Here is a video.

Other fire stuff

Are there certain plants that ignite more readily than others? Yes. Here is a nice article from Field and Stream that goes over the basics.

What about burning poison oak? Yes, that is bad too.

Wet cotton clothes are bad

Again, not a hack—but cotton is terrible when wet (so is denim jeans). When wet stuff is next to your body, the water evaporates. In this process the liquid water turns into a gas water (water vapor). The phase transition requires energy. Guess where the energy comes from? Yup, it comes from the human. This makes the human colder. Here is my more detailed explanation.

What about wool and other materials? The key to these better fabrics is that they “wick”—they pull the water away from the body. Here is a nice post on that.

Zipper for ice traction

MacGyver takes the tent zippers and uses them on people’s shoes for added traction on ice. It’s sort of like mini-spikes on your shoes. Classic.

How to make drinkable water

MacGyver uses a tree branch to act as a water filter. This seems to be real (from MIT) so you know it’s got to be good.

Here is a nice video showing how this would work.

Making rope (string)

I’ll admit it—I’ve never really understood how this works. If you take some vine or some other material, it has a certain maximum strength in its tension before it breaks. If you take two of these things together, it doubles the strength. If you take these two things and then twist them—the strength is more than double. What? But it does indeed work (I need to do an experiment sometime to really understand this).

Here is an older video in which I attempted to make rope from a TV guide.

Size and weight of 18 million dollars

This is a classic MacGyver estimation problem. How do you find the size and weight of a bunch of money? Why does it even matter? Well, one big thing is to find the density of the money. If the density is less than the density of water, then the crate of money would float and then be swept away in a flash flood.

Yes, you don’t need the weight and size—but just the density. However, if you want to estimate how long the crate was floating you DO need the size. Bigger crates will “hit the bottom” before smaller crates.

If you want to look at more stuff about the density of money, here is an older post in which I find out how far 1 trillion dollars would stack. Would it make it to the moon?

Surveying tools

How do you find the slope of the ground? This is where you need surveying tools. Here’s how it works. Get a scope (from a rifle) and make sure it’s aimed level. There are plenty of ways to level a scope—those little bubble levels work great. Next get a survey stick. Make sure this is also vertical and then measure where the scope points at the stick.

If you know the change in elevation and the distance between the stick and the scope you have the slope.

Float distance calculation

Yeah, this is pretty tough—but that should never stop anyone from trying. How do you estimate the distance a crate will float in a flood? Here are some things to consider (some of these would be tough to estimate).

  • How fast was the water flowing?
  • How deep did the water get?
  • How long did the flood last?

Really, if you know those things you can calculate the speed and time of the floating crate. This would then give you the distance. From that you can find the location on a map.

Drag sled

To move a crate (or an injured MacGyver), it shouldn’t be too hard to make a drag thing—called a travios.

Grab hot coals

Don’t try this at home, but it is indeed possible to grab hot coals. Essentially, you can grab hot stuff if you are really quick. There isn’t enough time to transfer energy to cause a major burn.

It’s just like walking on hot coals. Here is a nice physics post on that.

MacGyver Season 3 episode 12 Science notes: Fence + Suitcase + Americium-241

Toothpick in grenade

It’s not a super Mac-hack, but it works. The only thing MacGyver does is to put a toothpick in place a grenade pin. It only works for a little bit before the grenade explodes. However, the physics discussion is pretty good. Let’s go over some of the terms.

  • Tensile strength. This is essentially the maximum force a material can withstand when being pulled apart. Just imagine a rope—how hard can you pull on the rope before it breaks. That would be the ultimate tensile strength. Yes, wood has a pretty high tensile strength.
  • Compressive strength. How hard can you squeeze the thing before it fails? Something like concrete has a very high compressive strength, but not so much with tensile strength. Wood could have a good compressive strength if it’s wide and short. Long skinny boards of wood tend to buckle.
  • Sheer strength. This is the maximum force an object can withstand when two forces are pushing in opposite directions but not directly at each other. Think of scissors.

What is a dirty bomb?

This is another non-hack. However, I just want to describe the difference between a nuclear bomb and a dirty bomb. A nuclear bomb uses a nuclear reaction (usually started with conventional explosives) to make a massive boom.

The dirty bomb is NOT a nuclear explosion. Instead, it uses conventional explosives to spread radioactive material around. It’s dirty.


MacGyver builds a strong electromagnet to move a bolt inside a locked door. Yes, this is possible. You would need a strong electromagnet—that means high electric current and thus thick wires. You also need a fairly beefy battery to get this much current.

Oh, one possible problem. If the bolt is ferromagnetic (steel) and so is the door, then it’s going to be difficult to get that bolt to move. However, if the door is aluminum or some type of non-ferromagnetic material then this would work.

Wall walk

There are two methods to get over the pressure sensitive floor (they end up not using this though). There is a wall-walking stilt method and a rolling sled method. Both have the contact point with the wall at an angle—this is needed in order to work (because of physics).

Let me just start with a setup that would only barely work. Here is a view of a person using completely horizontal stilts along with the forces on the person.

The first problem is that the stick the reaches across the hall would have to fit perfectly. The harder it is pushed against the wall, the greater the frictional force. And it is this upward frictional force that balances the weight pulling down.

The second problem is with these horizontal arms. When they attach to the person, there is no upward force. This would be like trying to hold a rope with a weight in the middle perfectly horizontal. It won’t work.

Here is a better option.

This setup fixes both of the problems. The sticks can be longer than the hallway (and not fit perfectly) and there is now an upward component from the wall that helps support the human.

Mercury Switch

What is a mercury switch and how can you build something similar? Here, I made a video for you.

Smartphone Radiation Detector

MacGyver uses some smartphones (as usual) to detect radiation from the dirty bomb. This is essentially real.

A smartphone camera has a sensor that is normally used to detect light. However, this same sensor can be set off by other types of radiation—like the stuff that is produced by radioactive stuff.

In order to actually detect this radiation, you need to block the light from getting to the camera—electric tape over the lens will do the trick.

But wait! There is a real project that uses normal human smartphones to detect cosmic radiation. Check it out—the CRAYIS Project.

Rolling Tire Bomb

Yeah, mixing stuff and make explosions. The end.

MacGyver Season 3 Episode 11 Science Notes: Mac + Fallout + Jack

How do you break out of iron shackles?

So, Jack and MacGyver are stuck in a fallout shelter and they need to get out of shackles. Maybe they are just old iron or maybe they are old steel—either way, they need to get out.

There are several steel-busting options, but let’s go with something thermal. In this case he could do something similar to thermite (similar). How about glycerol and potassium permanganate?

Again, this is not thermite—this is the stuff that’s usually used to start a thermite reaction though.

Opening a door with thermal expansion.

MacGyver uses some butter knives and electric current to heat up a steel door. When the door expands it cracks the cement around it so that they can open the door.

Would knives heat up? Yes. When you short out an electric circuit, you get a bunch of current. Lot’s of electric current means that things get hot. This could theoretically heat up the door.

Now, if you are going to escape with this technique yourself you need to be careful. A steel door has a very large thermal mass. It would take some time to heat it up—but it would indeed heat up.

Do things expand when heated? Absolutely. Here, I made a quick demo for you.

Scuba shooting crossbow.

Yup. Basically this just takes some springs to store energy and then uses that energy to propel an empty scuba tank to break a door.

Zip gun

Jack has a small projectile in a tube with a spring—a zip gun. It’s basically a deadly sized nerf gun.

MacGyver Season 1 Episode 9 Science Notes: Chisel

There is no introduction, just science.

Lighter and spray can stun thing

MacGyver gets a broken spray can of something (it really could be any aerosol can) and attaches a cigarette lighter to it. He then makes it so the lighter burns while the spray sprays. When he throws it, boom.

Yeah, these spray cans can ignite stuff. This is plausible.

DIY hot air balloon for Jack’s phone

Someone needs to make a super clip of all the times Mac says “Jack, I need your phone”. I think that’s funny.

In this case, the idea is to build a mini hot air balloon to lift up the phone so that they can see a “bird’s eye view” of the city. Here’s how it works.

  • Get a thin plastic trash bag.
  • Get some fuel—in this case it’s that stuff that burns to keep food hot for a buffet or something. Oh, they put it in aluminum foil.
  • Hang the phone and light the fuel.

Boom. That’s it. Yes, it’s real. The basic idea is that the fuel heats up air that fills the bag. Hot air has a lower density than cold air—this means that the weight of the air inside the bag is less than the weight of air outside of the bag. This gives a net upward buoyancy force on the bag.

Here is a more detailed explanation of buoyancy, if you need it.

OK, but would this be enough to lift a phone? It would be tough, but it’s at least plausible. It depends on the weight of the phone and fuel, the size of the bag, the temperature of the inside and outside air. So, it’s possible.

Here is one you can make yourself.

Bullet proof paper

OK, it’s not bullet proof paper. It’s a calculation of how much paper you would need to stop a bullet. I love how well this turned out.

mythbusters bullet phonebook

Bullet proof shield

This one is simple. Yes, if you tape a bunch of kevlar vests to a door it will be fairly bulletproof. MacGyver’s calculation is great (I should know). OK, it’s not perfect—but it’s a good example how to make a basic estimation.

Personally, the dialogue gets to the basic point and the animations and graphics are really nice. LOVE IT.

Let’s go over some of the details.

  • You need some basic values—like the speed and mass of a bullet from an AK-47. I googled this, but maybe MacGyver just knew it.
  • From there, you want to somehow model the interaction between a bullet and paper. The first idea is to think of it like a drag force (just like a bullet going through air or something). Of course this causes a problem because that makes it a velocity dependent force and therefore VERY difficult to deal with.
  • But what if there is a constant force on the bullet during the interaction with the paper? In that case, we can use the work-energy principle (which MacGyver says—YAY!).
  • With a constant drag force, you can then find the distance over which this force needs to do work to stop the bullet.
  • For the constant drag force, I estimated the density of paper (a little bit lower than the density of water) and assumed this was the constant force. Of course this is wrong—but it’s just a place to start. You have to start somewhere.
  • Really, the rest is just calculations.

Here is my original estimation.

Oh, I guess there are a few things to point out. First, the MythBusters also looked at using paper to bulletproof a car. It sort of worked. Second, in the end MacGyver reports the paper thickness in inches. I hate imperial units—but I guess that’s just the way things are.

Still, super pumped at the way this turned out.

Improvised weapons

In order to fend off the attackers, MacGyver makes some improvised explosives to shoot marble cannon balls. I don’t want to go into the chemistry of explosives so I will just put my normal explanation.

Any time you mix two or more chemicals, it is plausible that it could make an explosion. The end.

Intercept radio transmission

MacGyver wants to figure out what the bad guys are saying on their radios. He uses a yaghi antenna to get a directional signal and then he connects it to an AM/FM radio and picks up the signal.

OK, they probably don’t broadcast on the AM-FM frequency range. However, it’s possible he could modify the tuner in the radio to pick up their frequency. It would help if he knew their frequency. Also it’s hopeful that they aren’t using encrypted radios.

Dish soap to slide a safe

This is basic physics. Dish soap can indeed decrease the frictional force—especially for smooth surfaces. This would make a great physics problem.

Sugar putty bomb

Again with the bomb thing—using sugar for an explosive. Well, you can make a rocket from sugar (again—from the MythBusters)

Radio detonator 

In order to detonate the explosives, MacGyver takes apart one radio such that it makes a spark when receiving a signal (instead of making a noise). This is fairly plausible.

There are a couple of other things, but I will stop here.

MacGyver Season 1 Episode 8 Science Notes: Corkscrew

Remember, I’m just going over the MacGyver hacks with science stuff in them.

DIY Blacklight

This one is fairly legit. MacGyver is in an escape room and needs to find a blacklight to read some hidden words on the wall. He says it would be easier to build a blacklight than it would be to find it.

Here is MacGyver’s build. Use a smart phone LED light and an old floppy disk. In theory, this could work. Here is the short answer: most white LED lights work by having an ultraviolet light with a fluorescence coating to produce white light (which is the way the old school tube-like fluorescent lights work). This means that the white LED also produces UV light (also called blacklight). You just need to block out the visible light—and that’s where the floppy disk comes in. If you take the actual disk out of the floppy, some of them block visible light.

I actually wrote a WIRED post on this—here it is.

Fluorescence of stuff on the wall 

The second part of this hack is to use the DIY UV light to read the stuff on the wall. Here’s how that works.

Electrified stair rail

A bad guy is getting away and running down a stairwell. MacGyver pulls some wires out of a wall light and touches one of the wires to the rail and the guy gets shocked and falls.

Would this work? Maybe. In order for the guy to get shocked, there has to be a complete electrical circuit that passes through the dude. That means the current would come out of the wall, go to the rail, go to the guy, go OUT of the guy, and then back to the wall.

In order to get through the guy, he would have to be grounded and the rail would have to NOT be grounded. I suspect that building code requires a rail to be grounded for safety—but you never know. In order to get the guy grounded, he would have to stand on conducting ground (like metal) and have terrible shoes.

But still, it’s at least possible.

Hacking magnetic lock

MacGyver is trapped in another room—with essentially nothing in it. He grabs some wire out of the ceiling panels can fishes out the wires for the security pad. Then he manually enters the keypad code by connecting wires.

OK, this could work. However, it if it’s a legit security pad it would probably be harder to hack.

Wine bottle rocket

MacGyver takes some wine bottles, dumps out some of the wine and recorks them. Then he pumps them up and let’s the cork pop out. Now it’s a water bottle rocket.

Here is the launch in slow motion.

Of course like many MacGyver hacks, this is real. The only problem is that it would take a normal person a few minutes to set up and not a few seconds.

Radio jammer

MacGyver needs to take out some remote controlled guns. He grabs a CB radio from a truck and hooks it up to a large power supply. This broadcasts enough static to jam the radio signal to the guns.

Let’s go over the details.

  • Could he get a CB out of a truck? Yes. Easy (but it wouldn’t be as quick as he does it).
  • Could he hook it up to a power supply? I think he used the power lines to some metal crusher. This probably wouldn’t work. The CB runs on DC current and the big power is probably AC. Also, it probably expects 12 volts.
  • Would this jam the signal? Here’s where he might get lucky. If the guns run on the same channel as the CB —it would work. If the power supply messes up the radio so that it just somehow broadcasts on a bunch of frequencies—it would work.

So, it’s possible.