Day: February 12, 2016

Air resistance

Air resistance

             Air resistance                  02/12/16
An interesting conundrums appears for students of physics when considering Newton’s first law. If objects are supposed to go on forever in the vacuity of a net force, then why do objects on Earth slow down in the horizontal direction? The answer lies in the fact that when objects move through Earth’s atmosphere, they experience a phenomena called air resistance. Because air is a fluid, solid objects can be suffused in it as a surrounding medium. Analogous to objects moving in water, when one moves through the atmosphere, it comes into contact with air particles, causing minor but emergent impinging effects on an object’s motion. When all of these collisions amalgamate, a phenomena known as a drag force appears. This drag force is what causes all of the impinging effects. Because drag force is based off collisions with air particles which in turn are based off Newton’s third law, the drag force is contingent on an object’s velocity, so the faster one moves, the more resistance one experiences. An application of this is terminal velocity in free fall, a peculiar phenomena that all objects in free fall experience. When an object is in free fall, it accelerates which in turn causes it’s velocity to rise, However, as it’s velocity rises, so does it’s drag force, and consequently the velocity of the object will reach an apex, with the drag force balancing out the gravitational force, therefore causing constant velocity as a result of Newton’s first law.