James, an idea for another show would be how the first scientists measured such things as the speed of sound, light, gravity, etc. with the limited equipment and knowledge they had at that time. Think about it, We all know and use them, but imaging how hard would it be for us now if the first scientists had never calculated them.
You should've used a police or ambulance siren as example for the doppler effect, I think many people unfamiliar with the doppler effect would find that is much easier to visualize in their head. Also, a sine wave picture that compresses and contracts would have been nice.
Very good. But, don't forget that the British set up the first national TV system in the 1930s in order to develop RADAR. Britain by 1940 had a thriving amount of technicians who could produce and maintain the CRTs needed, as well as the transmission systems, and allowed for the development of the Chain Home system. Clever.....
Great video! Gravitational Lensing takes advantage of a similar process. Using galaxies to bend and manipulate light waves as they travel towards the observer, we can look back billions of years into the past and take snapshots of the early universe in its formation. Keep up the great work!
Mr. May, it wasn't a "French Cruise Ship," it was the "SS Normandie," the French's best Ocean Liner of the Inter-War period. The M/V Kalakala was the first American civilian ship to receive RADAR in the spinning form, but that's another story.
It's convenient how MinutePhysics uploaded a 10 second video on RADAR not long ago, and Head Squeeze does a full scale video not long after. Coincidence?
Dear James May If you could explain to me why some radars are in a dome, others like a turning saucer and again some looking like a grid of girders, it would be greatly appreciated. Thank you.
Im not James May but quick answer: The dome is usually the structure the real radar is under. The saucer is just like a parabolic antenna, an old fashioned way to maximise antenna gain. The girders are just the structure of the antenna. The most weight efficient way to build sturdy stuff. To counter corrosion or stiffen the structure, a weather proof outer layer may be added.
Wise Guy 508 I don't think jammers cancel out incoming waves, I'm not sure that's possible. Because radars are dependent on sending out a click and calculating the time until the response, all you need to do to screw a radar's range finding capabilities off is just spam fake responses. the radar receiver will start picking up more responses than it sent and won't be able to differentiate between a real rebound and the fake ones throwing off it's ability to accurately gauge range.
It pumps out tons of noise and points it at the radar. Using the cliff analogy, it would be like a second person cranking up a radio station set on static next to your ear so that you can't hear the echo clearly. There are more intelligent jammers, but this is the basic idea.
TheGoodChap Well, what do you expect would have happened when the radar gets fired at a blank piece of sky? Does it fall apart right there and then? Because I'm not saying your theory is wrong, I'm just saying that there are a lot of cloudless days and our atmosphere alone doesn't reflect radar, so it probably doesn't rely on a click HAVING to come back.
How do you get accurate ranging with radio waves traveling at the speed of light? given the speed of light at 3*10⁸m/s a difference in 1ns would mean a difference of 2*0.3m = 0.6m (times two as the radio wave actually travels the distance twice.) Given that even the most modern cpus need several nano seconds per operation and you would require a whole lot of them, there isn't enough time to compute an accurate solution. Besides that, the beam is probably emitted longer than that, possibly with variation in length. I imagine you would get an ambiguity of at least 500m with that sort of technology. Also there are different kinds of radar, how do they differ? for example modern millitary uses doppler pulse radars, so I imagine they are using the doppler effect to give an output, but how exactly is it used and why do they have problems picking up objects that fly lower and orthogonal to the emitter?
+FalcoGer I'm not 100% sure about your question and am only an enthusiast, but my brother and I have had lots of talks about radar and that's his degree not mine....., but I believe the time difference wouldn't matter much in the case of two separate systems comparing their answers after the fact of detection. It would be fast, but yes, not instantaneous due to the limitations of the speed of voltage, which is much slower than the speed of light. (not to be confused with the speed of electricity). The wave is directional, so the receiver isn't picking up a beam transmitted from the source...whatever the pulse time would be. An analogy would be a laser pointer held by a friend and a mirror in the distance, with your eye beside the laser. You can't see the laser, only the reflection / mirror...and your friend knows the exact time he turned the laser on, and the exact time you saw it immediately.... YOU know. So then you two compare notes and get a difference in very small time scales. You can do the same thing yourself yelling at a cliff or brick wall with a stopwatch. The orthogonal thing, I think it has to do with the surface area that the radar can see. As you stated, teh distance does diminish the signal, and if not a lot of that signal is hitting the object, then less is returned and can't be seen. The surface area of the aircraft has a lot to do with that, which is generally less when seen from "the side". In stealth craft especially, angles make a HUGE difference, mostly likewise angles, so that radar reflects in an odd fashion. The amount an air-frame absorbs as radar matters too, reducing the signal returning, since they are similar to microwaves, you "can" turn these signals into heat and absorb them, the f117 made use of both of these facts.......which is why it looked like the black aircraft from hell. That and when you are looking at something toward the ground, you can get interference due to direct returns, and potentially the wave being attenuated by the ground depending on the frequency, making any image you get back a real mess. Ocean waves would work the same way, if not worse. Though, I think, using long wave radar and that surface attenuation, you can actually get radar to follow the curve of the earth too. All depends on the frequency really...and line of sight. The best case would be a way of attenuating the radar wave around an object to have no radar at all and no radar "shadow". But I think that's above my pay grade. :P
I am an uncultured American who rarely sees the light of day. What does "a Jessie" mean? Mr. May's used it in a clearly (and, playfully) derogatory way. I skimmed my "go to" reference sites for gaining context into language and came up empty handed. I would love to know the etymology of the colloquial use for the word. Thanks a head of time. By the way... This is a great channel. I Subscribed early into a playlist. If you love this stuff and don't already know about it, I encourage looking into an entire culture called "Nerdfighteria". We decrease "world suck". If that sounds like a worthwhile endeavor to you, I encourage you to search the term.
Recommend reading about Sir Robert Watson Watt. Conducted one of the first tests in England of Radar on 12 February 1935 at the town of Weedon near Daventry. Event is described in the Brian Johnson book "The Secret War." Book was published 1978.
Stealth is pretty straight forward. It's a mix of thing for high end fighter jets, but it all boils down to lowering the amount of radio waves that bounce off of the plane and return back to the sender of the signal. Think of it like trying to find someone in a black room with a flash light. The thing you're trying to find can be better hidden if you paint it in something that doesn't reflect the light, black in the case of light and a special radio wave absorbing layer in the case of Radar. It's dark so it's hard to spot it. This however is just part of what makes modern jets stealthy, they are also shaped in a way that make it unlikely that the signals that do bounce off don't bounce back to the sender, hence the jagged edges of a stealth jet. But it doesn't stop there. There's also measures taken to make sure that the jet exhaust is covered up so that no one could see the infra red heat signature. You know... like in that Star Trek movie where Kirk sends a missile which follows the Klingon's exhaust trail. The tough thing is that a jet can't use it's radar while staying quiet, because enemy jets can figure out where the source of the signal is and take you out.
The graphic at 5:00 is misleading: In the case of the top car, the dashes should actually be compressed, instead in the graphic they are lengthened as well.
I would like you guys to answer this question, as it has been annoying me for years: How is it that we tend to randomly make mistakes, no matter how much we practice or force ourselves not to do so, such as playing a video game, musical instrument or even talking to someone?
TheUKNutter interesting question, I'm not sure where we'd start with that one! If you've got any other burning questions join our G+ Community and tell us what you want to know plus.google.com/b/109745634756856970234/communities/115682880183087388642?cfem=1
At about 2:19 James May mentiones that the speed of radio waves is the speed of light. I was under the impression that sound travels slower than light. Can someone clear this up for me please?
Gotcha, that makes complete sense. I kept confusing radio with audio. And yes, I know what you mean about light not being waves, but instead photons. Either one is tough to prove, at least for now.
James answered the question 'What is an itch?' here and I think he talks about why it's so satisfying to scratch the itch! What is an itch? - James May's Q&A (Ep 5) - Head Squeeze
... And when we send out a pulse of sound and time it's return it's called Sonar, and when we send out a laser pulse and time it's return it's called LiDAR...
If you're referring to the "You'd die if you'd paint over your whole body" thing - it's a myth. :) Made up by Ian Fleming for 'Goldfinger'. In reality you'd just get a bit sweaty.
Actually it's true, you would die, but not necessarily for the lack of oxygen. you'd die from having your body temperature elevated excessively; check out James May's video on space suits (or was it some other video?) He even mentions that the actress painted gold had one side of her body left uncoated
Don Pedro Yep, I remember that. But I read on Snopes that they did that because they thought she would die, not because she actually would. Yes, you could die from your body temperature getting too high, but there are other ways to control body temperature.
BO L L O C K S
This dude explained radar really well.
One does not call Sir. James May “this dude”
@@zakwright9612 captain slow 😉
Yes, the script writer was good
No he didn’t.
When I think “Dude” I think shirtless skateboarder and/or surfer with long blonde hair giving a “Shaka” sign
Love how Jeremy is of course the "very loud mate" 😂
…i don’t think he is
@Edgar Draves I think there's a compilation floating around the Internet of him screaming at Hammond. Yeah, he is the loud one.
James, an idea for another show would be how the first scientists measured such things as the speed of sound, light, gravity, etc. with the limited equipment and knowledge they had at that time. Think about it, We all know and use them, but imaging how hard would it be for us now if the first scientists had never calculated them.
Gotta love the return of Jeremy Clarkson looking like he's just seen a G-Wiz
''A very loud mate. Clarkson? HA!
"Imagine you've installed a very loud mate"
Clarkson.
2:40 "The dirty Fokkers"
I SEE WHAT YOU DID THERE
I LIKE IT.
You should've used a police or ambulance siren as example for the doppler effect, I think many people unfamiliar with the doppler effect would find that is much easier to visualize in their head. Also, a sine wave picture that compresses and contracts would have been nice.
What more, jump from the cliff! :-)
I look forward to part 2 :)
Yes, me too.
I love that word Bollox as well.. 😁 Must have an X on the end though 😊
That seems like an experiment that Clarkson would be more than happy to assist on.
Thank you! First thing I've found that's explained simply and concisely ❤️
I can't be the only one who didn't find it boring. Fascinating really.
I ALWAYS HAVE COFFEE WHEN I WATCH RADAR YOU KNOW THAT
now that i have my coffee im ready to watch radar
darkodin7 I just put the last of 1500 fiber optic windows in my 2 foot star destroyer as I started to read your post. That's funny. Thumbs up!!!
10,000 years of fresh air. We must get through that air shield!
When is searched for „how does Radar Work“ i expected anyone but james may
a very loud mate= clarkson hehehehehe :D
"The Dirty Fokkers." Oh ho! Clever.
Is there a Radar Jamming Video?! I'd love to see one.
Nice addition of Jeremy Clarkson
When you drop a slinkey, why does the bottom of it hang in mid-air until the top hits the bottom?
Chain of energy
Because they're being pulled together like an elastic band
The English really have elocution down to an art form. I love listening to them speak.
Very good. But, don't forget that the British set up the first national TV system in the 1930s in order to develop RADAR. Britain by 1940 had a thriving amount of technicians who could produce and maintain the CRTs needed, as well as the transmission systems, and allowed for the development of the Chain Home system. Clever.....
Great video!
Gravitational Lensing takes advantage of a similar process. Using galaxies to bend and manipulate light waves as they travel towards the observer, we can look back billions of years into the past and take snapshots of the early universe in its formation. Keep up the great work!
Bending I understood but how does it manipulates?
Mr. May, it wasn't a "French Cruise Ship," it was the "SS Normandie," the French's best Ocean Liner of the Inter-War period. The M/V Kalakala was the first American civilian ship to receive RADAR in the spinning form, but that's another story.
Thanks for explaining the radar
It's convenient how MinutePhysics uploaded a 10 second video on RADAR not long ago, and Head Squeeze does a full scale video not long after. Coincidence?
Probably, this video more than likely took longer to make than Minute Physics video
FINALLY, someone explains it
don't forget to make part 2.
You know, this really could all be explained in 9.9999999... seconds.
So does sonar work the same way except in underwater?
2:41 Now that's one of his more funnier lines. 😆🤣
Right,I owned a radar shop, and I agree with you. The radar sold in my store is only available in the Russian market.
Jamming is flooding the frequency with random noise. Canceling a wave through phase shifting is something else entirely.
+Jim Fortune No. You just lit up your location like a christmas tree then.
matchbox2022 It's a bad idea in many situations, but that doesn't change the definition. Jamming is different from spoofing.
Awesome!
I love these science stuffs...thank you! Hope you got rich with this channel.
Really informative
Dear James May
If you could explain to me why some radars are in a dome, others like a turning saucer and again some looking like a grid of girders, it would be greatly appreciated.
Thank you.
Im not James May but quick answer: The dome is usually the structure the real radar is under.
The saucer is just like a parabolic antenna, an old fashioned way to maximise antenna gain.
The girders are just the structure of the antenna. The most weight efficient way to build sturdy stuff. To counter corrosion or stiffen the structure, a weather proof outer layer may be added.
how does a radar jammer work? :D
I'm guessing they use superposition of waves to cancel out the incoming wave so that the outgoing wave literally disappears.
radar jammer throws egg cartons at your swear words
Wise Guy 508
I don't think jammers cancel out incoming waves, I'm not sure that's possible. Because radars are dependent on sending out a click and calculating the time until the response, all you need to do to screw a radar's range finding capabilities off is just spam fake responses. the radar receiver will start picking up more responses than it sent and won't be able to differentiate between a real rebound and the fake ones throwing off it's ability to accurately gauge range.
It pumps out tons of noise and points it at the radar.
Using the cliff analogy, it would be like a second person cranking up a radio station set on static next to your ear so that you can't hear the echo clearly. There are more intelligent jammers, but this is the basic idea.
TheGoodChap Well, what do you expect would have happened when the radar gets fired at a blank piece of sky? Does it fall apart right there and then? Because I'm not saying your theory is wrong, I'm just saying that there are a lot of cloudless days and our atmosphere alone doesn't reflect radar, so it probably doesn't rely on a click HAVING to come back.
James may has got an amazing Brain
How do the fighter aircraft nose mounted radars scan at at the behind the aircraft?
This was worth watching just to add the word "telemobiloscope" to my vocabulary.
James showed his age on this video. But hey, who cares about that right? great guy and a great presenter.
What's the music at 1.06?.
Beautiful technology
I like how James says "Becaz"
How do you get accurate ranging with radio waves traveling at the speed of light? given the speed of light at 3*10⁸m/s a difference in 1ns would mean a difference of 2*0.3m = 0.6m (times two as the radio wave actually travels the distance twice.) Given that even the most modern cpus need several nano seconds per operation and you would require a whole lot of them, there isn't enough time to compute an accurate solution. Besides that, the beam is probably emitted longer than that, possibly with variation in length. I imagine you would get an ambiguity of at least 500m with that sort of technology.
Also there are different kinds of radar, how do they differ? for example modern millitary uses doppler pulse radars, so I imagine they are using the doppler effect to give an output, but how exactly is it used and why do they have problems picking up objects that fly lower and orthogonal to the emitter?
+FalcoGer I'm not 100% sure about your question and am only an enthusiast, but my brother and I have had lots of talks about radar and that's his degree not mine....., but I believe the time difference wouldn't matter much in the case of two separate systems comparing their answers after the fact of detection. It would be fast, but yes, not instantaneous due to the limitations of the speed of voltage, which is much slower than the speed of light. (not to be confused with the speed of electricity).
The wave is directional, so the receiver isn't picking up a beam transmitted from the source...whatever the pulse time would be. An analogy would be a laser pointer held by a friend and a mirror in the distance, with your eye beside the laser. You can't see the laser, only the reflection / mirror...and your friend knows the exact time he turned the laser on, and the exact time you saw it immediately.... YOU know. So then you two compare notes and get a difference in very small time scales. You can do the same thing yourself yelling at a cliff or brick wall with a stopwatch.
The orthogonal thing, I think it has to do with the surface area that the radar can see. As you stated, teh distance does diminish the signal, and if not a lot of that signal is hitting the object, then less is returned and can't be seen.
The surface area of the aircraft has a lot to do with that, which is generally less when seen from "the side". In stealth craft especially, angles make a HUGE difference, mostly likewise angles, so that radar reflects in an odd fashion. The amount an air-frame absorbs as radar matters too, reducing the signal returning, since they are similar to microwaves, you "can" turn these signals into heat and absorb them, the f117 made use of both of these facts.......which is why it looked like the black aircraft from hell.
That and when you are looking at something toward the ground, you can get interference due to direct returns, and potentially the wave being attenuated by the ground depending on the frequency, making any image you get back a real mess.
Ocean waves would work the same way, if not worse.
Though, I think, using long wave radar and that surface attenuation, you can actually get radar to follow the curve of the earth too. All depends on the frequency really...and line of sight.
The best case would be a way of attenuating the radar wave around an object to have no radar at all and no radar "shadow". But I think that's above my pay grade. :P
James May For real
Good
I am an uncultured American who rarely sees the light of day. What does "a Jessie" mean? Mr. May's used it in a clearly (and, playfully) derogatory way. I skimmed my "go to" reference sites for gaining context into language and came up empty handed. I would love to know the etymology of the colloquial use for the word. Thanks a head of time. By the way... This is a great channel. I Subscribed early into a playlist. If you love this stuff and don't already know about it, I encourage looking into an entire culture called "Nerdfighteria". We decrease "world suck". If that sounds like a worthwhile endeavor to you, I encourage you to search the term.
Recommend reading about Sir Robert Watson Watt. Conducted one of the first tests in England of Radar on 12 February 1935 at the town of Weedon near Daventry.
Event is described in the Brian Johnson book "The Secret War." Book was published 1978.
Lol how ironic this is posted right after VSauce did a vid on swearing
Coincidental, not ironic (:
***** Lol my bad!
drew2pac Ironic meaning, being mostly made of iron.
***** ...... True! God, it's like we all have subscribed to the same channels...... Which is kind of ironic!
The ironic bit was a joke btw :)
drew2pac Since we all seem to be subscribed to the same channels, got any subscription suggestions? lol
How are tornadoes formed?
we want stealth and radar jamming
Stealth is pretty straight forward. It's a mix of thing for high end fighter jets, but it all boils down to lowering the amount of radio waves that bounce off of the plane and return back to the sender of the signal. Think of it like trying to find someone in a black room with a flash light.
The thing you're trying to find can be better hidden if you paint it in something that doesn't reflect the light, black in the case of light and a special radio wave absorbing layer in the case of Radar. It's dark so it's hard to spot it.
This however is just part of what makes modern jets stealthy, they are also shaped in a way that make it unlikely that the signals that do bounce off don't bounce back to the sender, hence the jagged edges of a stealth jet.
But it doesn't stop there. There's also measures taken to make sure that the jet exhaust is covered up so that no one could see the infra red heat signature. You know... like in that Star Trek movie where Kirk sends a missile which follows the Klingon's exhaust trail.
The tough thing is that a jet can't use it's radar while staying quiet, because enemy jets can figure out where the source of the signal is and take you out.
This was put out such a long time ago... Hi 2020 people!
The graphic at 5:00 is misleading: In the case of the top car, the dashes should actually be compressed, instead in the graphic they are lengthened as well.
The note "or light waves" is a bit misleading, as radio waves are technically a part of the light wave spectrum, just not the visible part.
love your videos!
He says that radio waves are reflected by solid objects but if you are in a concrete room, you still get cell reception.
How does that work?????
your Batik is cool, Sir !
I would like you guys to answer this question, as it has been annoying me for years:
How is it that we tend to randomly make mistakes, no matter how much we practice or force ourselves not to do so, such as playing a video game, musical instrument or even talking to someone?
TheUKNutter interesting question, I'm not sure where we'd start with that one! If you've got any other burning questions join our G+ Community and tell us what you want to know plus.google.com/b/109745634756856970234/communities/115682880183087388642?cfem=1
***** I'll have a look when I have time! It's New Year's Eve, so... :D
@@TheUKNutter its been 8 years but did u get to find the answer to your question yet>??
@@surajprakash3181 Haha nope. Even now it still pisses me off.
@@TSOTL-0302 This account is 12 years old, but I have another one that’s 15 years old!
“Bollocks is my favourite one” 😂😂😂
I was so curious about the radar on EXO's teaser that I ended up here. 😅
I was searching for "Radal" and this video showed up
"Dirty Fokkers"
RIP 😂😂😂😂
Guys, can clouds help to reduce an aircraft's radar signature?? Or is there no effect on radar by clouds?
How to jam: trough a fragile container containing jam at an radar array, if the container brakes, you jammed the radar
You savev the jamming system for another time. It has been 4 years, mate.
"BOFFINS" LMAO
First i see the mythbusters guys appearing on CZcams on tested and now top gear is here
That's because television is dead and no one except grandmas in rest home and mental patients will be watching TV in 20 years.
ben garcia me too
Good topic! So....how is radar calibrated??
We've come to a halt in technology advances cause of the lacks of hole makers
What about synthetic aperture radar, radar imaging, and radar satellites? That's the COOL radar!
make also a vid about noise canceling, please
The outro song?
haha Jeremy Clarkson @ 3:28 :D
the blip on the animated background blinks OUT OF SYNC with the refresh impulse.
Bravo.......cover Megatron......cheers
... in the world!
Wait? Captain Slow?
It is him.
Stormtrooper Elite Not only him, but we (sort of) also get Jezza at 3:27.
DreamPen By Jove, it is him! I never noticed that
Cool stuff ;)
At about 2:19 James May mentiones that the speed of radio waves is the speed of light. I was under the impression that sound travels slower than light. Can someone clear this up for me please?
Gotcha, that makes complete sense. I kept confusing radio with audio. And yes, I know what you mean about light not being waves, but instead photons. Either one is tough to prove, at least for now.
head squeeze; guest staring a grumpy jeremy clarkson at 3:28
Hello, Head Squeeze. Can you make a video with presenter Mr. James May, explaining how heavy water is made?
Teach us the ways of stealth please.
James may is a vampire in a conspiracy against circles and stones and mice. Circles are they best. Squares are not.
Yeah, I'm here because of EXO.
Thanks for the info 😊
Can you talk about how the internet and wifi works please :)
Top Gear?
Why do the stars shine/twinkle in the night sky?
How do we calculate the Universe's age?
Why does scratching feel so good?
James answered the question 'What is an itch?' here and I think he talks about why it's so satisfying to scratch the itch! What is an itch? - James May's Q&A (Ep 5) - Head Squeeze
... And when we send out a pulse of sound and time it's return it's called Sonar, and when we send out a laser pulse and time it's return it's called LiDAR...
Bg song name?
How long does it take to die if all your pores are covered?
If you're referring to the "You'd die if you'd paint over your whole body" thing - it's a myth. :) Made up by Ian Fleming for 'Goldfinger'. In reality you'd just get a bit sweaty.
Oh. Haha, thanks.
YayItsScarlett No problem. I also thought that was true til they talked about it on QI.
Actually it's true, you would die, but not necessarily for the lack of oxygen. you'd die from having your body temperature elevated excessively; check out James May's video on space suits (or was it some other video?) He even mentions that the actress painted gold had one side of her body left uncoated
Don Pedro Yep, I remember that. But I read on Snopes that they did that because they thought she would die, not because she actually would. Yes, you could die from your body temperature getting too high, but there are other ways to control body temperature.
Can radar detect a land mass while sailing on the ocean?
Yes.
It's simple,I live.
Does a radar compensate for the curvature of the earth? Or the earth is flat?
what about sonar?
I wish May was my teacher
Stealth ships actually are not stealthy. They just appear insignificant for their size as a fishing boat or similar.
+FalcoGer Right yeah nothing to do with the radar-absorbent surface or the material used to build them lol