- published: 07 Jul 2014
- views: 576986
In kinematics, the speed of an object is the magnitude of its velocity (the rate of change of its position); it is thus a scalar quantity. The average speed of an object in an interval of time is the distance traveled by the object divided by the duration of the interval; the instantaneous speed is the limit of the average speed as the duration of the time interval approaches zero .
Like velocity, speed has the dimensions of a length divided by a time; the SI unit of speed is the meter per second, but the most usual unit of speed in everyday usage is the kilometer per hour or, in the USA and the UK, miles per hour. For air and marine travel the knot is commonly used.
The fastest possible speed at which energy or information can travel, according to special relativity, is the speed of light in vacuum c = 299,792,458 meters per second, approximately 1079 million kilometers per hour (671,000,000 mph). Matter cannot quite reach the speed of light, as this would require an infinite amount of energy. In relativity physics, the concept of rapidity replaces the classical idea of speed. In day-to-day athletics, it is proper to say that a teenager can achieve atleast 20 kmph (or 12.43 mph) of speed while a best runner can achieve 30 kmph (or 18.64 mph) which is similiar to run 100m running race in about 12 seconds. The average speed for a teenager is 24 kmph, which can be a result on running 100m in 15 seconds.
"Soul and Fire" by Sebadoh
Written by Lou Barlow
from _Bubble and Scrape_
It's all a matter
of soul and fire.
Infatuation
or true desire.
The thrill of discovery,
divine intervention;
cruel, cruel change,
pain of rejection.
As you walk away
think of all the joy we shared.
If you decide you need me,
I'll be wondering if I care...
Not there to soothe your soul,
friend to tender friend.
I think our love is coming to an end.
King persuader,
congratulations.
You share her heart,
you bought her soul
Princess confusion
come to me again.
Saying goodbye
was so much fun.
When you walk away
feel the freedom in your heart.
There's a joy in letting go,
free to find a love apart.
When I lose control
I need a kind, forgiving friend,
but I think our love is coming to an end.