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Newton's three laws of motion are so integral to everything around us that many people take them for granted. Young children achieve a basic understanding of these laws as they interact with the world around them, but older children, teenagers, and even adults can achieve a deeper understanding and an appreciation for these laws through model rocket kits. This article explains how a school project using Estes model rockets can be used to teach Newton's second law of motion.
Newton's second law of motion states that force is equal to mass times acceleration. These may sound like scary "physics" words, but do not let that overwhelm you. Let's apply these terms to model rocket kits.
Force is a power or energy exerted on an object. When that force is exerted, the object will exert a force of its own in return. With perfectly balanced forces, nothing in the situation will move. This is known as a static situation. Imagine pushing your hand against a brick wall. When your hand exerts a force on that brick wall, the wall "pushes" back with an equal force, and nothing moves at all. This situation is examined in Newton's third law.
However, in a dynamic situation, the forces are unbalanced. This means that the force exerted on an object and the force returned by the object are not equal. Because these forces are not equal, the object will move. Model rocket kits offer a great way to demonstrate this law.
Mass is the scientific term for all the "stuff" that makes up an object and is measured in grams. On the surface of Earth, mass and weight are generally treated the same way. However, outside of Eart's gravity, an object will have the same mass but will clearly have a different weight.
Anytime the speed of an object changes, the object accelerates. If the object moves at a greater speed, this is known as positive acceleration. If the object moves at a lesser speed, this is known as negative acceleration (or deceleration).
All of these forces can be seen in the motion of Estes model rockets. Prior to the rocket's launch, the rocket will be in a static situation where the forces are balanced. When the fuse is lit, the fuel will burn and will produce force that propels the rocket upward.
The rocket's mass can be measured prior to a launch. Estes model rockets with more or less mass will react differently to equal amounts of force and acceleration.
The rate at which the speed of a rocket increases (or decreases) is the rocket's acceleration. Different engines and differing amounts of fuel can be used create differing amounts of acceleration. Model rocket kits provide a great illustration of different amounts of acceleration.
The effect of force, mass, and acceleration on the path of a rocket can be varied with different types of Estes model rockets, different types of engines in the rockets, and differing amounts of fuel. These "experiments" can be repeated to analyze the effects of more or less force, mass, or acceleration.
Model rockets are an entertaining way to gain a deeper understanding of Newton''s laws of motion. Rather than being a difficult or boring experiment in a lab, model rockets encourage a student''s sense of adventure. Experimenting with model rockets provides an entertaining forum to analyze these ideas!
