Empty plastic/glass bottle with a lid
Fill the bottle with water until it reaches 2/3rd level.
Use the funnel and put 3-4 tablespoons of glitter in the bottle and tightly close it.
Turn the bottle upside-down and quickly move the bottle in a circular motion for 10-15 seconds.
Stop moving the bottle after 15-20 seconds and observe the mini tornado forming inside the water.
How does it work?
Spinning the bottle in a circular motion creates a water vortex which looks like a tornado. The water continues to spin around the centre of vortex because of centripetal force.
Centripetal force is an inward force directing an object or fluid towards the centre of its circular path. The spinning in the water is visible clearly due to the presence of glitter in water. The glitter acts as dust and debris which are found spinning in an actual tornado.