# MacGyver Season 1 Episode 21 Science Notes: Cigar Cutter

Dirty Bomb

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.

$E = mc^2$

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.

The “sec” in parsec is for “seconds of a degree”—not time seconds. Yes, they made a mistake in Star Wars. Here is even more details about measuring distances in astronomy.

Blood Stopping Foam

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.

https://www.dailymail.co.uk/sciencetech/article-2697428/The-injectable-foam-stop-soldiers-bleeding-death-battlefield.html

It would be sort of like that expanding foam you use to seal cracks around your house—except for blood.

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.

Check it out.

# 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— https://phys.org/news/2015-03-cyanide-poisoning-seconds.html.

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 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 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 3 Episode 7 Notes

Computer Recycling

This is unfortunately real.  There are places where all the old computer crap ends up and people try to get the good stuff out of them.  Here is a WIRED story.

I guess a more important issue—why do we throw away so much stuff?  Perhaps it’s just because we live in an era of rapid technology changes.  This means that computers can become outdated fairly fast.  It’s cheaper to just throw stuff away rather than deal with it properly.

Actually, at one point there was a student project that looked into the financial benefit of getting the useful stuff out of old electronic stuff—in particular the gold.  How do you get it out and is it worth the money?  I think the answer is no—you probably won’t make money by mining electronic stuff for gold.

Take apart a hard drive

This isn’t a hack from the show, but I just have to add a comment.  If you have an old hard drive, you should take it apart.  It might not be super easy since many of them have those stupid “security screws”—but still you should go for it.

There are two great things you can get out of a hard drive: awesome magnets and great mirrors.  The magnets are really what the hard drive is all about—using the magnets to make magnetic fields that write magnetic domains.

There isn’t really a mirror inside the hard drive, but in most cases the hard drive platters (the spinny thing that the data is written too) is super smooth.  So smooth that it works as a mirror.  Be careful.  Most of these platters are metal, but I did find one that was glass-like and shattered when I dropped it.  The metal ones make great mirrors though.

Toothbrush lock pick

Let me just say that I have a friend who is a locksmith.  After talking to him, it’s very clear that just about every lock can be picked.  It’s not even that hard.  Really, locks are more of a social contract than actual physical barriers.

If you want to try picking locks, there are plenty of guides online (and there is the classic MIT lock picking guide.  There are essentially two parts to lock picking.  First, you need to torque the lock cylinder with a torque wrench.  Second you need to jiggle the lock pins (inside the lock) up so that they get stuck up.  Then you can open the lock.

The toothbrush is just a quick quick to jiggle the pins up to open the lock.  I think I’m going to build one of these—you know, for research purposes.

Exploding toothbrush

Actually, I’m not sure what device is used here—but it looks like an electric toothbrush.  MacGyver takes the toothbrush and connects it to an AC power cord and then jams it in the lock.  It explodes.

Of course, it’s not the toothbrush that explodes, it’s the rechargeable battery.  Yes, these things can explode.  More on this later.

Microwave gun to disable cars

Here is the short version of this hack.  MacGyver is in the back of a dump truck with junk in it.  They are being chased by bad guys in military trucks.  OK, they aren’t bad guys—but they want to stop MacGyver.  Really, they are just doing their jobs, right?

OK, so MacGyver finds an old microwave and takes it apart.  He gets out the magnetron and then plugs it into the truck DC power supply.  This creates directed microwaves that he aims the microwaves at the trucks and they get disabled (with fire).

Is this real? Like most MacGyver hacks (but not all), it’s at least based on something real.  Yes, there are microwave guns that can disable a car – https://www.technologyreview.com/s/409039/stopping-cars-with-radiation/ These microwaves then screw up the electronics in the car.  I think it works by generating electric currents in the computers that melt tiny wires.  Well, it’s real anyway.

What about the microwave gun?  Yes, that is also real—I mean, you have one in your microwave.  Check out this microwave (real) gun from Allen Pan.

That dude is the real MacGyver.

High frequency sounds and younger humans

Some kids are being held captive by some adults.  MacGyver needs to send them a message—but he obviously doesn’t want the bad guys to hear it.  So, he hacks a tape record so that it plays a high frequency message.  Here is the deal: younger humans can detect sounds at much higher frequencies than adults can.  I think it has something to do with the frequency response of the ear-thingy (which probably has a technical name too).

Oh, what about hacking the tape player?  I think that it’s possible to record a message and then play it back at a higher frequency.  Really, all you need to do is speed up the motor that pulls the magnetic tape over the reader head.  I think that would do the trick.

Lithium battery bombs

Here is another hack that is unfortunately true.

https://www.bbc.com/news/technology-37255127

If I understand it correctly, it seems like there is some type of internal short in the battery that causes it to heat up.  When it gets hot, it gets more internal shorts and heats up even faster.  You get some type of runaway reaction and boom.  Bomb.

If you want to make tiny grenade like bombs out of these things, good luck.  It’s pretty tough to make them explode exactly when you want them to.  Oh, don’t do that anyway.