Equilibrium basically means "balance". It is the point where two things cancel themselves out. Think about two people in a tug-o-war contest. If one person pulls harder, the rope (and opponent) moves to the side, but if both pull just as hard everything would stay the same - that is equilibrium.
The goal of this project is to see what affects the equilibrium in a milk carton.
Make sure you get your parents permission before beginning this experiment - Plus your Dad or Mom may want to join you in doing them!
Supplies Needed:
1) Empty Milk carton (plastic jug or 2 litre bottle will work also)
2) Pencil (to poke holes in the jug)
3) Ruler
4) Paper to record your results
Step 1:
Using the pencil (or felt pen) and ruler mark the carton every two inches.
Carefully punch holes in the the milk carton with your pencil at each of the marks you made (start 2 inches from the bottom of the carton). Be sure the holes are all the same size.
Now place the milk carton into the kitchen sink (or another large sink where you won't make a mess)
Turn the faucet on and start filling the milk carton very slowly.
Watch to see how high the water will go.
Did the water reach the second hole? Third?
Now fill it a little faster . . .
How high did the water reach this time?
How fast does the water have to be filling it to make the carton overflow from the top?
Now you can try adding holes, or covering them up (with scotch tape) to see what happens!
Watch below as the water fills my cartoon barrel.
Can you guess how far the carton will fill up with water?
Read more about equilibrium on our page about carbon dating.
