## Thursday, February 21, 2013

### Inertia and Birds

Geeky fun ahead!  This post has physics and geometry in it.  And WALL-E.  And baby birds.  Just to give you a heads up.

An object at rest tends to stay at rest.
An object in motion tends to stay in motion.

This is the law of inertia.  Both states—rest and motion—are a type of rest.  It takes work to shift an object out of rest and it takes work to stop an object in motion.  Work is the application of force.  Work resists or opposes the natural tendency of an object.  Friction, air resistance, and gravity are all forces in abundance on earth and so the law of inertia isn’t as obvious here.  It is impossible to build a perpetual motion machine because of friction, even though perpetual or continual motion seems to be necessary to the law of inertia.

In space, however, inertia is more easily observed.  Just watch the scene in WALL-E where WALL-E and EVE are dancing outside the Axiom.  WALL-E uses the fire extinguisher to move himself.  Without the force of the goop leaving the extinguisher, he can’t move.  And without applying an opposite force of the goop, he can’t stop.

Also, when the space shuttle went on a mission, it was the changing from rest on the surface of the earth that took the most work.  The space shuttle had to expend energy to leave the earth.  Resting on the earth did not take energy.  And orbiting the earth did not take energy.  Even though the space shuttle was traveling at 17,580 miles an hour, it was simply in a controlled perpetual fall.  Even though one state involves motion, both are a type of rest.

Now for the birds.  When birds are born, the mother bird has made a nest and lined it with what she could find to make it as soft and comfortable as possible.  The chicks need to stay in the nest as they grow.  They need to stay at rest.  And they tend do, since leaving the nest at this stage involves falling to their death—either on impact or as a meal for another animal.  When the birds have grown and it comes time for them to learn to fly, the mother bird takes out the comfortable lining and makes the nest pokey.  She gives the grown chicks incentive to take the leap and learn to fly.  If necessary, she applies force to change them from their tendency to rest and to shift them into motion.

From the chick’s point of view, what is going on?  The nest is all they’ve ever known.  They’ve never used their wings.  How do they come to trust them?  Before, jumping out of the nest meant death, how do they switch?  Do they even realize that they have wings before they jump?  What they need to do is just jump and stick out their wings.  The wind does the rest.  It’s a controlled falling.  It’s easy, once you’re doing it.  But how do you start?

Leap to what you think is your death.  Spread out your wings, or arms.  And the wind, or Spirit, does the rest.

That seems like how a lot of things in this life of faith work.  Submit to what you don’t understand, can’t explain, can’t control, can’t do on your own.  Just yield.  Take your leap, then ride the wind.  It’s not a matter of trusting my wings, but of asking if I even have them.

Specifically, in life right now, I don’t know what I’m doing.  I’m standing on the edge, and I’m not really sure if it’s time to jump.  Does the jumping involve a job change?  Which side of the nest should I jump out of?  When should I jump?  I don’t know.  But it’s getting increasingly uncomfortable, so it’ll probably be soon!

And do not seek what you are to eat and what you are to drink, nor be worried.  For all the nations of the world seek after these things, and your Father knows that you need them.  Instead, seek his kingdom, and these things will be added to you.
Fear not, little flock, for it is your Father’s good pleasure to give you the kingdom.  Sell your possessions, and give to the needy.  Provide yourselves with moneybags that do not grow old, with a treasure in the heavens that does not fail, where no thief approaches and no moth destroys.  For where your treasure is, there will your heart be also.
Luke 12:29-34

And I think, “Where is my heart—in the nest or in the wind?”

And the Spirit says, “Do not worry.  Seek your Father’s kingdom—it is His good and joyous pleasure to give it to you!”

We are a little flock of grown baby birds.  He knows what we need, and that we should stick together, and seek our Father’s kingdom together.  And we should bring tangible good news and food and clothing to the poor, freedom to those bound up.  We, little flock, should break oppression.  It is still the year of our Father’s favor!  There is no hesitancy or reluctance in Him—He knows what we need and joyously provides abundance.  Little flock, let us together give out the abundance of our Father’s house, not worry about our needs, and rest in our Father’s great love for us.

Special thanks to my friend Vinnie for the inspiration for this post.

For this Lenten season I am giving up perfectionism and posting a blog each day, Monday through Friday, from Ash Wednesday on February 13th, through Easter, on March 31st.  For more information, read “What Are You Giving Up?  Jesus died for me and loves me, and this is an exercise in remembering that.  Thanks for joining me!

photo credit: Leo Laporte via photopin cc

#### 1 comment:

1. it is a leap to the death: death of a chick's nest-confined life. Never going back... except possibly to build another place of leaping.