Practice English Speaking&Listening with: Loop de loop question | Centripetal force and gravitation | Physics | Khan Academy

What I want to do in this video is show you a very cool video, then pose a question.

But I want to make sure that everything is up and up,

in terms of the copyright laws.

So the video I want to show you is from the show called the fifth gear,

that appears on channel 5, I believe in the United Kingdom.

I think I'm okay on good copyright grounds to claim

fair use here, because

obviously the point of this is I'm going to ask a math question

about the vide were going to see

and so fair use

laws

the purpose and character of use

including whether such a commercial nature or non profit educational

purposes we're definitely the later

non profit educational purposes

we are actually

we aren't trying to in any way replace the work being used

I'm just going to show a little snippet of it

so we can use it as the basis for a problem

this is kinda the meat of fair use law

the viewer may fairly cite from the original work if it is

design if his design be really and truly to use the passages

for the purposes for fair and reasonable criticism

in this case

it's fair and reasonable math problem or physics problem

on the other hand it is as clear he thus cites the most important parts of the work. with the view not to criticize

but to supercede the

the use of the original work and substitute

the review for it

such a use will be deemed in law a piracy

so in no way do I want to supersede it. You should go look it up, go watch the show.

this is not good enough

I don't even have the sound on

it's going to be a small window over here

where I'm just going to show this

really really

the part where they actually do a loop

de loop.

now with that out of the way

this is where you can find more about fifth gear

which is on channel 5

so now let me show you the video

I'm going to have the sound down and so this is the video over here

this is a pretty neat video

this guy is going to try to do a loop de loop and he's actually going to succeed

at doing the loop de loop

and what I want you to do, the question I want to pose

is look at this video

and get a stop watch out

or whatever else you need out a ruler whatever else you might need to do

and try to figure out what

we're going to try to figure out two things

we're going to find out the minimum velocity the car needs to do the

loop de loop

and we're also going to try to figure out what his actual velocity was

over the course of the loop de loop

so let's actually just watch this video

so there he goes

he's starting

he's accelerating

it looks like he's

just crossed

he's pushing almost forty miles an hour

at least I'm assuming that's miles per hour

this is a British show

and then he

hits

the loop de loop

and then he finishes it

and he's done

so let's think about for the next video

let's think about if we can figure out what the minimum

what the minimum velocity or i should say the magnitude of the velocity

or the speed had to be

to actually

complete the loop right over here and then we can actually get a stopwatch later on to

see what his actall velocity was