Thursday, June 16, 2005
Ahhhhhhhhhhhhh!
Question:
You learn in school that gravity pulls you down at about 9.8 m/s^2. If you jump out of an airplane you would accelerate at this rate and in theory in about 30 seconds you would be going more than 1000 km/h. But in fact a skydiver only reaches about 200 km/h.
Hints:
What you learn in school is the simple situation which has no air friction.
Air resistance is increases with the square of the velocity, as you go faster and faster the air resistance keeps increasing until it is a strong as your weight and stop your acceleration.
In other words, if you are heavier (denser) your terminal velocity will be a little higher.
-What would happen if air friction where only linear to velocity?
Links:
Hyperphyics.
You learn in school that gravity pulls you down at about 9.8 m/s^2. If you jump out of an airplane you would accelerate at this rate and in theory in about 30 seconds you would be going more than 1000 km/h. But in fact a skydiver only reaches about 200 km/h.
Hints:
- The skydiver accelerates for a while then slows the acceleration, and then stops accelerating at a terminal velocity.
- It has to do with the air resistance of course
- Air resistance increases with the square of the velocity (basically), there's a cubed component as well that it usually ignored.
What you learn in school is the simple situation which has no air friction.
Air resistance is increases with the square of the velocity, as you go faster and faster the air resistance keeps increasing until it is a strong as your weight and stop your acceleration.
In other words, if you are heavier (denser) your terminal velocity will be a little higher.
-What would happen if air friction where only linear to velocity?
Links:
Hyperphyics.
# posted by Scott Kirkwood @ 11:09 AM 
