How did kitt get inside the semi?

djshag69 · Post by **djshag69** » Wed Oct 01, 2003 5:35 pm

Me and many co-workers of mine and friends have always wondered how kitt actually got inside the semi, while both were moving. Now imagine if kitt was going 40 miles an hour and the semi about 35, as soon as kitts wheels hit the semi he would take off and still be going 40 miles an hour and hit it like a ramp and go through the semi. So i assumed maybe he brakes, but i have watched the rear of the car, the brake light don't ever go on. So you think they do it at slow speeds or speed it up? Because it is physically impossible to actually do that without braking, and not to mention how smooth it looks on tv.

Benjamin Knight · Post by **Benjamin Knight** » Wed Oct 01, 2003 5:39 pm

The semi and KITT most likely matched speed before docking and I think KITT's parking space inside the semi and maybe the ramp had some kind of system which slowed down KITT. Like planes landing on a aircradt carrier!

P.S. Who drives the semi, is it controled from the back and or auto-cruise??

Post by **Michael Pajaro** » Wed Oct 01, 2003 6:00 pm

You've come to the right place, as this is an old subject for us. It is NOT physically impossible, in fact it is quite easy to drive a car up a moving ramp. The key is to keep in mind conservation of momentum; KITT always stays the same speed RELATIVE TO THE GROUND. So when he hits the ramp, he slowly drives into the Semi at 5 mph.

Here's one of our previous discussions on the topic, but as far as I'm concerned I don't mind going through the explanation again in this new thread if you have any more questions. It's one of my "pet subjects" I never get tired of, although other people may.

http://www.knightrideronline.com/phpbb/ ... 40&start=0

Mike

Cougar · Post by **Cougar** » Wed Oct 01, 2003 7:51 pm

Ben,
I asked this question a while back. During the eary episdodes we saw the semi parked on the side of the road, so probably Bonnie drove it. But later on when Bonnie was in the back and the smei was moving we never saw anyone. I guess we were to just know [i]someone[/i] was driving it but it was not important who.

knightimmortal · Post by **knightimmortal** » Wed Oct 01, 2003 8:10 pm

There is absolutely no proof that Bonnie ever drove the semi, sorry, but there isn't. There was always a an unnamed driver, but once again, there still is no proof that Bonnie ever drove the semi.

KI

nivek · Post by **nivek** » Wed Oct 01, 2003 8:11 pm

I ask this same qestion along time ago like when I frist started here.

djshag69 · Post by **djshag69** » Thu Oct 02, 2003 8:39 am

I mean i understand the concepts, i can observe what is happening, what i wanna know how is it physically possible to go from say 50mph to 5mph on the ramp, i believe it is physically impossible and some trick wss used.

Post by **Michael Pajaro** » Thu Oct 02, 2003 11:18 am

You have to keep the same frame of reference. Here's another way to think of it. Suppose KITT is driving back from a mission, and is 50 miles from the Foundation. How long will it take him to get home? If he ignores the Semi, it will take him one hour because he is moving at 50 mph. If instead he decides to ride home in the Semi, how long will it take him to get home? A little more than an hour, because he's moving at 45 mph.

If Bonnie were back at the Foundation monitoring KITT's position, she would see a blinking red dot moving at 50 mph while KITT was on the road, and a blinking red dot moving at 45 mph once KITT drove into the Semi.

The only place the 5mph figure comes into play would be on KITT's speedometer, but that's simply because speedometers usually measure how fast the wheels are spinning and not the actual speed of a vehicle. If you've ever driven in mud or ice, you know that you can get easily get your speedometer up over 50 mph and have your car be completely stopped.

As further "proof" that driving up a moving ramp is a simple matter of physics, they did that exact stunt on an episode of Fear Factor. The contestants had to start out at 50 mph in front of a car carrier, then quickly drive behind the truck and on to the trailer. They had no stunt driving experience at all, no training, no practice, and were under pressure to do the stunt as quickly as possible. Two of the 3 people succeeded with no trouble. (the 3rd missed the ramp slightly on approach).

Mike

nivek · Post by **nivek** » Thu Oct 02, 2003 2:50 pm

But that isn't what happens at all. If you had a skateboard in your car and let it go at 50 mph, it would continue along the road at 50 mph. It maintains its same forward momentum, regardless of the frame of reference. The same thing happens with KITT driving in or out of the Semi

well, with that skateboard thing um you would have to make sure you do it the same way as kitt, and I think you might be sure shocked in what happen. it will not be going 50 mph when it leaves the ramp it will be going the little slower then then the speed it was going on the ramp. yes the ramp is going 50 mph one why but you are back out so you are going another why so you wheels are spinning so the wheels will keep spinning the same way as what they where when they left the ramp. so in return you are only going the speed that you going down the ramp minis some.

knightimmortal · Post by **knightimmortal** » Thu Oct 02, 2003 3:00 pm

Let's state at least one law of physics that governs this entire situation here.

A body at rest will remain at rest, a body will remain in motion unless an outside force is exterted upon it.

Now...let's take into consideration our turbo charged skateboard.

If you shoot a skateboard out a moving car at 50 mph, the skateboard won't remain at 50 mph, because of the frictional and gravitational forces acting upon it. It will get a slowdown, until an eventual stop.

Now take into consideration KITT going up the ramp.

There are quite a few unknown variables here.

-To remain at a 50 mph speed, Michael would have to accelerate into the ramp.
-Who is to say that he doesn't just coast, and in fact gently tap the brake going up to slow down, specifically once part of the car is up the ramp.
- The brake would be an additional slowing force, so that when Michael is actually up on the ramp, he is going no faster than 5mph, because the moment that any part left the road, the forward motion of speed was decreated exponentially, from the frictional and gravitational forces already acting upon the car.

Oh I remember this now... *nudges Mike*

I wonder how many times we are going to end up debating minute details of the same thing before we realize it this time. (For the newbies, this particular question got rather large, hot and heavy a few years back.)

KI

Post by **Michael Pajaro** » Thu Oct 02, 2003 3:06 pm

You're absolutely right that the turbo skateboard (sounds fun!) would slow down to a halt. But when you first release it, it is travelling at 50mph, the same speed as the car. Nivek and Transparent seemed to be suggesting that it changes reference frames and so would be released at 0 mph or would be rolling backwards relative to the road. And that is definitely not what happens.

nivek · Post by **nivek** » Thu Oct 02, 2003 3:11 pm

I was think that you would send it down a ramp like kitt does when backing out of the semi. so it would out of the back of the car or truck.

djshag69 · Post by **djshag69** » Thu Oct 02, 2003 3:22 pm

I don't think im am wording what im trying to say correctly then. Let me try it this way. Im in kitt, driving behind the semi going 50mph, the semi is going lets say 45, the ramp in the back is open and im trying to get in the semi. IM going 50, as soon as i drive into the semi, my car is still going 50 mph, there is no law in physics saying if i am going 50 miles per hour im going to just automatically slow down to 5 mph, the point im trying to make is. Driving behind the semi at 50mph, as soon as i go onto the ramp, friction will only slow me down so much, but i would have to break to slow down and go inside the semi at a smooth 5mph. By observing what happens it makes sense, but even if you are going 50mph and you let momentum take you into the semi you would enter the semi at about 40, which would cause your to go right into it. How did they enter the semi without using the breaks?

knightimmortal · Post by **knightimmortal** » Thu Oct 02, 2003 3:30 pm

What says they entered the semi without using the brakes?

Why would they want to not use the brakes?

I think that is where the main point of your debate lies, because there is nothing that denotes that they don't use the brakes. In fact, when KITT goes into the semi, the brake lights are in fact on, all the way up.

Also, a car does not maintain 50 mph up an inclined plane without accelerating.

KI

Darknight · Post by **Darknight** » Thu Oct 02, 2003 3:43 pm

I think what's important to consider here is whether or not KITT's throttle stays at the same position. If KITT comes onto the ramp with his throttle still open at the same level as at 50, then he will get traction and go shooting through the semi. However, if KITT (or Michael) lets off the gas just before the rear wheels touch the ramp, then it's ok, because KITT's momentum will carry them part of the way up the ramp.

Simply coasting aboard at 5-10mph groundspeed above that of the semi is the best way to board the semi. Mike and I had quite a misunderstanding some time ago because we were saying the same thing two different ways. It is a fascinating subject, however, because most of us will never actually get the chance to try this at full speed, so we like to imagine how it would be.

DK

Post by **Michael Pajaro** » Thu Oct 02, 2003 4:35 pm

djshag69: I think you're confused about "relative velocity".

Supopse Bonnie is standing at the far end of the Semi (the wall away from the ramp) and is looking out across the ramp, watchnig KITT approach the Semi. From her perspective, KITT is approaching her at 5 mph. KITT may be driving 50 mph and she is riding along inside the semi at 45 mph, so the RELATIVE speed is 5 mph. If KITT smply drove on by the Semi, without going up the ramp at all, to Bonnie it would look as if KITT were driving by at 5mph.

That's where the 5 mph comes from. KITT never changes speed (aside from minor changes because of friction and climbing the ramp.) The entire time, both before and after he hits the ramp, KITT is going both 50 mph AND 5 mph, depending on the perspective of the observer.

djshag69 · Post by **djshag69** » Thu Oct 02, 2003 4:55 pm

the relative velocity statement is 100% correct and it makes perfect sense to me. the relative velocity happens with bonnie inside no matter what. Listen to this, if kitt is going 50 miles an hour behind the semi, it looks 5mph to bonnie, but as soon as all 4 wheels hit the ramp, kitt cannot in anyway still go 50mph or he will go right through the semi. Like you said if he starts going 5mph as soon as all 4 wheels are on it will look the same to bonnie. My question is, because on a couple of shows i have seen kitt enter the semi without using breaks, my quesion is not with relative velocity, it is, how can kitt slow down so much just with the wheels hitting the ramp and having friction involved, from 50 mph on the road to 5 mph when all 4 wheels are on the ramp of the truck. I hope that makes sense.

Post by **Michael Pajaro** » Thu Oct 02, 2003 5:42 pm

djshag69 wrote:as soon as all 4 wheels hit the ramp, kitt cannot in anyway still go 50mph or he will go right through the semi.

I absolutely understand what you're saying, because many people have the same confusion. You're saying that KITT immediately jumps up to 95 mph relative to the ground, because his 50mph gets added to the Semi's 45mph. That's not what happens.

You're suggesting that there is some absolute force at work that insists that KITT's speed always stay constant relative to the ground underneath him. So if he's on a flat highway he's doing 50mph, if he's on a moving ramp he's doing 95mph (50+45). But there is no such force. The tires don't care whether or not the ground underneath them is moving or not. They will spin at whatever speed is necessary to maintain the same forward momentum of the car.

When KITT's front tires hit the ramp, do they continue spin at 50mph? No, they almost instantly spin down to 5mph (with a small screech) because that's all the speed they need to maintain KITT's momentum. The same thing happens with the drive wheels in the rear. When they hit the ramp, they spin down to 5 mph to maintain KITT's momentum.

_Mad_Man_2k · Post by **_Mad_Man_2k** » Sat Oct 04, 2003 12:59 am

Turbo skateboard

Anyway, who cares? It's on TV, not many things are what they seem on TV. And it's just a plot element, not a scientific problem requiring hundreds of hours of debate, secretly plotted by the creators of the show to cause many fans to waste half their lives debating the physics of a stunt.

knightimmortal · Post by **knightimmortal** » Sat Oct 04, 2003 1:05 am

Because debates like these still keep forms of the show alive. These debates are a whole lot more interesting to some people than others.

KI

djshag69 · Post by **djshag69** » Tue Oct 07, 2003 11:00 pm

First off just cause some off us are intersted in different aspects of knight rider and just don't watch it like 3 year olds, doesn't mean you have to badger us. your right it does keep the forums going. and i asked my physiscs teacher and he said it is possible. bascially its a smiple problem, with a ball going towards the ramp with the foce being the speed, and the ramp projection, and all. i guess it would be a lot easier to understand watching it, but thanks for the input, ill try finding his email and copying it into the next post.

nivek · Post by **nivek** » Tue Oct 07, 2003 11:11 pm

yes please do post that email. I been meaning to ask my dad but just keep forgetting to