 Welcome back to Kids Fun Science. My name is Ken. Today's experiment is the life-size Leonardo's Arch Bridge. Last experiment I did the model size. This time I am going to cross the pond. As always, adult supervision is required. What you need for this experiment is 10 2 by 3 inches 8 foot boards and 5 1 and a quarter inch dowels. 48 inches long that you can find at your local hardware store. Alright, well welcome back to Kids Fun Science. Last experiment I did Leonardo's Arch Bridge. I did a little small model and so today what we're going to do is we're going to do a large life-size model and what we're going to do is we're going to go and create this and we're going to cross the pond. So we're going to make an actual bridge and cross the pond and this is how we do it. So to build the bridge I started off with two 2 by 3s and put them in the middle spacing them out about you know a three feet and then you're going to take one dowel and put it right in the middle of the 2 by 3 so about 4 feet in and so it's hanging over the edge then you're going to take two more 2 by 3s and place them on top of the dowel just like this overlapping about by 6 to 8 inches or 15 centimeters to 20 centimeters and then you take another dowel one person's going to grab the bottom two of the 2 by 3s lift them up so someone else can put the dowel in between extending over the dowel by 6 to 8 inches and then you're going to repeat the process go on the inside of the 2 by 3s and place them on top of the dowel and then you're going to grab one person is going to grab the bottom two 2 by 4s that are on the ground pick it up and place the dowel back in again with it extending over about 6 to 8 inches there so you're just gonna keep repeating it since my bocce ball court is right out of space on one end I'm trying to decide I think I'm gonna have to go the other way so I will grab two more and we're gonna place these on the inside of the other 2 by 4s but on top of the dowel right there and then we're gonna have Craig grab the bottom two move the camera here for a second grab the bottom two of the 2 by 4s that are on the ground right there it's gonna go down a little farther and then I'm gonna place the dowel once you get some higher than the other one and put them in about 68 inches up and therefore now we need to tighten it up a little bit you want to push all the 2 by 4s so they're kind of touching each other you don't want any space in between otherwise you won't be able to go across the bridge so when you step on it remember this is a just trying a little test run here you can see it's angling a little bit and it's going to tilt to the side so I stop going the base of the sides are not centered up so I need to pull those out a little bit and make sure it's completely set so now what we're gonna do is we're going to move the bridge once we get it tightened up we're gonna each grab one end of the bridge it should stay together and we're gonna move it over to the pond actually I only used four eight of the 2 by 3s and four of the dowels because my bridge my pond wasn't as long so here goes the first test and I'm starting to go in it's starting to sway back and forth and once again when we put it down the ground isn't a seed right there one of the 2 by 3s that was a close close call falling in there tilted to the side because it wasn't when we moved it we didn't tighten the 2 by 3s together so it had some space to be able to tilt so we're tighten this up and we're probably gonna have to move it too because the ground is not level so we're gonna move it so it's on level ground both ways you don't want it angling one way or the other and it kind of was angling so make sure it's a little straight here again and once everything's tight together then I will make the attempt to go across the pond without falling in so we'll get everything straight there make sure those dowels are a little bit farther up and remember I'm a hundred and ninety one pounds 86 kilograms and I'm going to attempt to go over here the steps are a little bit far but I think I'm going to now I'm in the middle now I'm fully committed and up one more step to go and did it success hundred ninety one pounds awesome so we got a second person going over so we can make it across the hardest part was how far the steps were in between so you had to really be flexible stretch maybe cutting the wood in half and making them closer instead of eight foot long two by three is making them four by four feet long you'd have steps in between once again success we made the bridge all the way across and it was successful so a little closer look here you can see that the dowels about six to eight inches over you could also see the two by fours are flushed against each other very important I hope you enjoyed this video remember to click thumbs up and share and thanks for watching