Imagine you’re playing a fun, summer game of badminton in your backyard.  Your sister smacks the birdie across the net directly at you and, whoosh!  You hit it back.  For a moment, it looks like it’s going to fly right into the neighbor’s yard, but then it slows and falls, barely crossing the net.  

Did you know that the fastest projectile in sports is the birdie, or shuttlecock?  At starting speeds of 300 miles per hour, professional badminton players can smash a birdie faster than a football or baseball.  Seconds later, it’s falling to the ground.  This has to do with the unique design of the shuttlecock and the laws of physics.

Why?

You will see that a shuttlecock is designed with a heavier rubber tip and a widening plastic “net.”  No matter how you hit the shuttlecock, its rubber end always turns to point forward. When you smack the birdie, it becomes a projectile, causing it to fly forward.  Then two invisible forces act upon it—air resistance and gravity.

 If there were no opposing forces, your birdie would keep going and going. Instead, two  forces slow your birdie down.  As the shuttlecock travels, wind or air resistance, called drag, catches the large surface area of the birdie’s plastic skirt.  The second force working against your flying birdie is gravity.  Gravity is a force between two objects, in this case Earth and your shuttlecock.  Earth’s gravity pulls your birdie down to the ground. 

Physics in Engineering 

As you can imagine, these forces are not just important in yard games. Engineers must consider air resistance when designing airplanes.  A streamlined plane creates less drag than one shaped like a box; it also flies farther with less fuel. An airplane must generate enough lift to stay in the air, overcoming the pull of gravity.

Physics in Creation

Throughout creation, we see wonderful examples of flying creatures that are designed to reduce drag.  The magnificent frigatebird has long, narrow wings that allow it to soar for hours with very little effort, allowing it to conserve energy.  Studies of birds like these have given engineers valuable lessons in designing efficient aircraft.

See it in Action

You can experiment with drag and gravity by creating paper airplanes.  Try folding several designs and see which design flies farthest.  As you might expect, a sleek, narrow design might fly better than a broad, flat design.  Why?  Less opposing force!

Physics Everywhere!

I remember a couple of times when one family member used these forces to her advantage.  When our daughter was about 7 years old, she’d play badminton with herself!  She’d smack the birdie and then run quickly to the other side, knowing the air resistance and gravity would give her time to get there to return the birdie. As she lobbed the shuttlecock back and forth, we marveled at her speed and coordination, never realizing that she was getting a hands-on physics lesson!