How to Bend a Laser Beam

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what's up guys XM 360 here and i have a

really cool and unique video for you

guys today i'm going to be showing you

guys two different methods on how to

bend a laser beam so this first method

is a bit easier than the second method

but it's also a bit less impressive all

you're going to need is your standard

laser pointer I'm using a laser 303 it's

a green one and you're also going to

need a large bottle something like a

2-liter soda bottle and it has to be

empty and you should also wear a pair of

laser safety glasses that way you don't

risk harming your eyes so the first

thing you're going to do is you're going

to cut a very small hole using a knife

or some scissors and you're going to do

it about maybe hat a little lower than

halfway down on the side of the bottle

so you can see I put mine right here so

once you have that hole cut

approximately the same size as the one I

cut right there you're either going to

cover up that hole with your finger or a

piece of tape and you're going to fill

up that bottle full of water and you're

going to leave the cap off and you're

going to position it next to a sink like

you see mine positioned right here then

you're simply going to let that hole be

open so that the water flows out just

like this and make sure you don't have

that cap on because that will affect the

flow of water once you have a constant

flow of water coming out what you're

going to do is you're going to position

your laser on the other side of the

bottle and as you guys will see when I

shine the laser through it's hitting my

hand on the other side and it's going in

a straight line however if I match that

beam up perfectly with that little hole

where the water is coming out it'll

actually get stuck inside that flow of

water and it'll go down into the sink

instead of going straight so this is

called total internal reflection the

beam is basically bouncing off the top

of the water in the bottom of the water

and it's just continuing this process

getting trapped inside of that flow of

water and I'm going to show you guys a

diagram - that really illustrates it

well so that's all there is to the first

method it's called total internal

reflection and moving on to the second

method this one takes a bit more time

and effort and supplies but it's

definitely more rewarding in the end

because you can really see the light

bending so to start what you guys are

going to need is a very small five

gallon fish tank and you're going to

want to use a rectangular one like this

I picked this one up at Petco for like

$13 so they're not really that expensive

you're also going to need to have two

pounds of granulated sugar and you're

going to need five litres of water so

you're going to need to be able to

measure leaders so they usually sell

these little two pound bags of sugar

they're very cheap you can probably get

it for a dollar or two and obviously you

guys will also need a laser

and some laser safety glasses so what

you're going to do is you're going to

use the entire two pound bag to fill up

the bottom of the fish tank break up any

big clumps of sugar and try to disperse

it evenly so that it's all level and

then you guys are going to put in the

five liters of water but you're going to

want to use maybe a folded piece of

cardboard or something like that because

you want to get the water to hit the

side of the tank so that it gently flows

in and doesn't disturb the sugar too

much so you guys will see I have my

container of water and then I'm just

using a folded piece of cardboard to get

the water to hit the walls of the tank

so that it gently flows in and kind of

leaves the sugar where it is because you

want the sugar to stay in a layer like

that on the bottom and you want it to

just kind of disperse into the water

over time instead of just a rough mixing

up of sugar and water so once you put

the five liters of water in this is the

tough part you got to wait two days

really that's how long I wait I mean

you'll be able to see it a little bit

after a couple hours but if you want the

full effect that you see in this video

you're going to want to wait at least 48

hours and as you guys can see because I

added that water gently I have that

layer of sugar still on the bottom

that's going to dissolve slowly over the

48 hours and what this is called this

method it's called a index of refraction

basically what's happening is the sugar

at the bottom is slowly dissolving

causing different layers of sugar water

concentration and that causes the light

to act differently in these different

layers so you're going to get the effect

that you see right here it's really cool

and really neat to try out and this

would make a really cool science project

basically the light is going through the

lighter concentration areas and higher

concentration areas at a bit different

rates so it kind of it kind of gives it

a bending effect now one very important

part of this is that you want that water

in the tank to stay perfectly still

during that 48 hours you don't want it

to get shooken up on a tilty table or

anything like that because that will

mess up those layers so make sure you

put it somewhere where it'll stay

perfectly still and it won't get stirred

up now I'm going to show you guys what

this looks like with several different

wavelengths of lasers but it definitely

works best with green lasers and blue

lasers 532 nanometers and 445 nanometers

those are the brightest to the ones that

you can see the best and they have the

best well-defined line but anyways guys

that's pretty much all there is to this

method it's called index of refraction

and when you're cleaning out the tank I

would suggest maybe pouring it outside

because that sugar water solution can be

very sticky and it can get caught on

your tank and

drains so I would pour it outside and

then kind of wash it out in the sink a

bit but anyways guys if you found this

video helpful or informative in any way

hit that like button down below and if

you have other ideas for laser

experiment videos that I should try

comment them down below and if you're

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just like this and as always guys thank

you for watching from x-m 360