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Milk carton water wheel science experiment – an experiment to demonstrate Newton’s Third Law.

1954 Lehigh Valley Dairy Milk Carton ALlentown PA

How to make a milk carton water wheel

Ever held a toy under your running bath water? Did it spin or twist away from you? This is explained by a law proposed by a guy named Sir Isaac Newton. Specifically, the law states that ‘for every action there is an equal and opposite reaction’.

  1. Poke a hole in the bottom left-hand corner of each of the four faces of a half-gallon, paper milk carton.
  2. Now poke a hole in the top flap of the milk carton. Tie a string through this hole.
  3. While covering the holes in the milk carton, pour water into the carton.
  4. Suspend the carton in the air by holding on to the string only.
  5. Now take your fingers off of the holes (did we mention that this should be done outside or over a sink – oh well, too late now).

Newton’s Third Law states that every action has an equal and opposite reaction. Water shoots out the holes and pushes back on the carton with equal force. A turbine is formed as the energy of the moving liquid is converted into rotational energy.

Milk carton water wheel science experiment notes

In the 1600’s, the English scientist and mathematician Sir Isaac Newton proposed three laws of motion. Newton’s laws concern the ideal motion of objects and do not take into account air resistance or other friction. However, these laws have enabled scientists to describe a wide variety of motions.

The third law of motion states that for each action there is an equal and opposite reaction. For example, when hot gases escape from a rocket engine during take-off, the rocket is propelled upward. The downward motion of the gases from the rocket generates a reaction of the rocket upward. This reaction helps the rocket overcome air resistance and fly into space. There are many other examples of Newton’s third law. When a rifle fires a bullet, the firing of the bullet is the action, and the recoil of the rifle is the reaction. Both are caused by the expanding gas of the exploding gunpowder. Rotating lawn sprinklers propel a spray of water in one direction while rotating in the other direction.

Sometimes the reaction is such that it cannot be easily seen. When you throw a ball against a wall and the ball bounces back, you do not see the wall moving in the opposite direction. But there is a small motion of the area of the wall that was hit. If the ball bounces from the ground, the earth also draws back, but the mass of the earth is so great that we cannot see its motion.

De motu corporum in gyrum (from Latin: “On the motion of bodies in an orbit”; abbreviated De Motu)


Newton arrived at his set of three laws incrementally. In a 1684 manuscript written to Huygens, he listed four laws: the principle of inertia, the change of motion by force, a statement about relative motion that would today be called Galilean invariance, and the rule that interactions between bodies do not change the motion of their center of mass. In a later manuscript, Newton added a law of action and reaction, while saying that this law and the law regarding the center of mass implied one another. Newton probably settled on the presentation in the Principia, with three primary laws and then other statements reduced to corollaries, during 1685. You can read a translation of De motu corporum in gyrum below.

Milk carton water wheel science experiment required supplies

Supplies: String, Milk carton

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