 and hold it over your plants to water them. Hello and welcome to Do Try This At Home, brought to you by the Institute of Physics. We're making these videos because we want to help parents and carers in the UK and Ireland to get their kids excited and curious about the world around them, even when you can't leave the house. My name's Melissa and welcome to my living room. Now, even with our famous British brain, sometimes my plants need a little bit of extra help, but I don't own a water sprinkler, so I've come up with an invention, the milk carton water sprinkler. To make your own water carton sprinkler, you'll need a piece of string, the length of the string is entirely up to you, an empty carton, it could be a milk or a juice carton, whatever you have to hand, a pair of scissors, and a bowl. Any type of bowl that you have will work just as well, be it a washing up bowl or even a bucket. So with this next part, be very careful when doing this with family members because we're going to be using our scissors as a stabbing tool to create our holes, coupled by the double wabby that we're going to get water absolutely everywhere. So I do recommend you carry out the experiment either in the kitchen or somewhere outdoors. What I did earlier was make a hole in the bottom left corner of each side of the carton like this. Next, at the top of your flap, create another hole, then get your string, thread it through the hole, and then tie a knot, and there you have it. So grab your carton and your bowl, fill it up with water, and then head out to your designated sprinkler zone. Pour the water in and watch it spin, and hold it over your plants to water them. So what's going on there and how can you explain it to your family? At the bottom where I've made my hole, the water is under pressure. The water above is pressing down on the water below, and this creates a force that pushes the water out of our holes, which is good for my plants. Now let's get to the bottom of why it spins. Looking at the milk carton from above with the string in the middle, when you make a hole, the water comes out here, which causes a pushing force on the opposite side of the carton here. Now it's important that the holes are in the corner, not the middle. If I push here and here, nothing happens. By making the pushing forces off-center, the carton spins around the string in the middle. There are four streams of water coming out of our carton in four different directions. The result is that there are four forces on our carton, pushing it around, which causes it to spin. If you're not completely sure about the science, don't worry. As always, test it out, have fun together, and then you can look it up together later on if you need to. Thanks for watching and see you next time.