ten little fingers - arvind gupta (4 mb pdf)

How to break a strong string?SOME AMUSING EXPERIMENTSCan you tie a knot?Tie one end of the string to your left forefinger, andthen put it around the hand as shown Now take thestring half a metre lower with your right hand and turnit 4 or 5 times round the right hand. Close your handsinto fists Now quickly move your right fist down andyour left fist up. The string will break at point A.Days in a monthThis picture will helpyou to remember thedays in each month.You imagine the namesof the months on yourknuckles and the placesbetween them (from leftto right). All themonths, which are onthe knuckles, have 31days; the others have30 days, exceptFebruary. February asyou know has 28 days,but once every fouryears, that is in a leapyears it has 29 days.Put a piece of rope on thetable. Ask a friend to takeone end in each handand tic a knot. Yourfriend must not let goany of the ends. It seemsimpossible, but you cando it easily. The trick is tofold your arms first andthen pick up the rope asshown in the picture.When you unfold yourarms, you will find yourknot in the centre of therope.Illusion with a pencilTake a pencil andhold it with yourfingers near oneend. Then youmove your handup and down nomore than 5centimetres. Holdthe pencil easilyso that it moves asyour hand goes upand down. If youdo it the right way,it will seem as ifyou are holding arubber pencilwhich bends allthe time.Plastic Straw through a potatoPut the cork in the CentreHole in your handHold a raw potato and a straw asshown. Your finger must cover thetop opening of the straw. Strike thepotato quickly with as much forceas you can, but be sure that thestraw is perpendicular to thepotato. After some practice youwill be able to put the strawthrough the potato.Fill a drinking glass with water andfloat a small cork in it. Ask yourfriends to make the cork stay in thecentre of the water - it must nottouch the sides of the glass. Theywill find that the cork always movesto the side of the glass. Now youadd more water so that it is slightlybulging up. The cork now moves tothe centre, where the water ishighest.Roll up a piece of paperto make a long tube. Sightthrough the tube at anobject. Now place yourhand as shown. You willsee a big clean hole in themiddle of your hand!