Floating Rice Bottle | STEM Activity

I am sure you have heard of the term, Friction many times in your daily life. But do you know who to explain it to your kids with a vivid demonstration? Our experiment Floating Rice Bottle is a good idea for you.

Age: 3+           Time: <10min

 Safety 

1. Be careful with the fragile glassware.
2. Adult supervision.

 Materials List 

• Bottle
• Rice
• Wooden stick
• Funnel

 Instruction 

Step 1/2 – Fill the bottle with rice and tap the bottom of the bottle on the table.  As you tap, the rice will pack down in the bottle. Add some more rice and continue to tap. Until the rice reaches the mouth of the bottle.  (If the bottle is not fully filled, the bottle will not go up with the stick)

Step 2/2 – Force the stick into the rice and Gently lift your chopstick which will stick firmly to the bottle.

 Troubleshooting 

Why did I fail to lift my bottle? 

—It is mostly because your rice is too loose, the stick is not deeply forced into the rice, or the bottle is not fully filled with rice.

 Scientific Description 

It is all about friction. Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. When you force a stick into the bottle of packed rice, it takes up extra room inside of the bottle. In such a small room, rice is pushed together to make room for the wooden stick and they are rubbing against one another. When the rice is packed so tightly together, the friction between the rice and the wooden stick is strong enough to hold the stick, allowing you to lift up the bottle with the stick. 

 Extensions 

You can replace the rice with other small stuff, like sand, bean and etc.