Did you manage to work out last weeks

Did you manage to work out last week’s puzzle? Stick the two books together. You can’t use glue or sticky tape. You don’t need to tear the books or fold the pages! You don’t need any other equipment or materials, just the two book.

How to do it…. 1. Overlap the back covers of the notebooks at least halfway. 2. Overlap the pages of the books together, flipping pages over one another. The more pages you do this with, the stronger it will be. 3. Try to pull the books apart. This works with most books, but the thicker the book and the more pages you overlap, the better. Watch the You. Tube video to see how it’s done. BE CARFEFUL IF YOU TRY THIS AT HOME – YOU MIGHT WANT TO USE OLD BOOKS SO YOU DON’T DAMAGE THEM. https: //www. youtube. com/watch? v=LVVs. PAJd 4 u. A

Why does it work? It’s all because of friction. Where the pages touch and overlap we get friction. The more pages we overlap, the more friction is produced. Friction tries to stop things moving, so if we generate enough friction it is very difficult to pull the books apart. If the experiment is done with two thick phonebooks a lot of friction is made and it is very difficult to pull them apart. Watch the https: //www. youtube. com/watch? v=qj. Kp. Qxl. Il. Uw You. Tube video to see how difficult it is….

On the next page is another science puzzle. Try to work out how to do it. If you do try it at home be careful not to spill the rice!! The solution to the puzzle is on the page after the challenge.

Challenge 2 Move all of the rice into the tub using a pencil. Don’t spill any of the rice in the bottle. You can’t use your hands to help you lift up the bottle.

How to do it… Challenge 2 1. Fill the bottle with rice so it is nearly full. Tap the bottle as you fill it. 2. Push the pencil as far as it will go into the bottle. 3. Lift up the bottle by holding the pencil and place the bottle of rice in the tub. Watch the video to see how it’s done. https: //www. youtube. com/watch? v=qo. Gzk 9 Gdn. QQ

Why it works It’s all to do with friction again. Friction is a force which tries to stop things moving. We get friction when two surfaces touch and rub together. Tapping the bottle as you fill it is the important step. This allows you to pack as much rice into the bottle as possible. As you press the pencil into the bottle, the grains of rice are pushed even closer together. As the grains of rice rub against each other and against the pencil they create friction. The force of the friction is enough to stop the pencil moving when you pull it upwards.