The egg drop experiment – a science project where students craft ways to keep an egg from breaking when dropped from a certain height – is a highlight in most physics classes. Read on to learn more about the basic, yet fundamental concepts the experiment demonstrates.
TL;DR (Too Long; Didn't Read)
The pull of gravity, free fall, air resistance and terminal velocity are all key physics concepts you'll learn about in the egg drop science project.
The Pull of Gravity
Gravity is the force that exists between the earth and objects near it. There are two criteria when defining gravity:
Force of gravity: Represented by Fgrav, this is the force that acts upon objects on or near the earth’s surface. The force of gravity can be calculated by the equation:
Acceleration of gravity: Represented by g, this is the acceleration experienced by an object when gravity is the only force applied to it. All objects on or near the earth’s surface have the same value for the acceleration of gravity (g): 9.8 m/s/s (meters per second per second).
A free-falling object is one that's falling under the sole influence of the force of gravity. There are two characteristics that define an object in free fall:
- The object does not encounter air resistance.
- All free-falling objects fall to the earth at a rate of 9.8 m/s/s.
Air resistance occurs when the leading surface of a falling object collides with air molecules. The two most common factors that can change air resistance are the object's speed and its cross-sectional area; an increase in either increases air resistance.
When an object in free fall meets air resistance, the equation is:
where Fnet is the difference between the force of gravity and the force of the air resistance.
Terminal velocity is the steady speed of an object freely falling through a gas or a liquid. As an object falls and meets an increase in air resistance, eventually the air resistance balances the force of gravity. Therefore, the force of air resistance is proportional to speed; air resistance increases as the speed of the object increases until terminal velocity is reached.
Egg drop experiments make learning about physics fun, approachable and stimulating. Definitely enjoy, but don't forget to apply these important fundamentals while crafting your project.