Physics majors?
Explain.
Physics majors?
Explain.
How our school system has failed...
Is there a disadvantage uphill?
BUMP
Whats really going to blow his mind is heavier bikers have an advantge on flat terrain as well.
... and teachers are demanding more pay. This is a bit like Ford cranking out the Pinto and proclaiming that if we paid more for cars they would do a better job.
people in glass houses wrote:
Whats really going to blow his mind is heavier bikers have an advantge on flat terrain as well.
As to my way of thinking there should be no advantage and actually a disadvantage. Objects of different weights accellerate at from the force of gravity (in a free fall) at the same speed. Larger bodies create more wind resistance hence the larger body has a disadvantage.
Not sure though about the role of momentum in cyling as it relates to weight.
...Because there isn't sufficient pay to attract quality teachers and get them to make a career in education.
If you're qualified to teach chemistry, you could making a hell of a lot more money in private industry than in a classroom teaching kids about valence electrons.
Mr Conundrum wrote:
Physics majors?
Explain.
It doesn't take a physics major bro. Galileo proved that weight doesn't increase acceleration in free fall (remember the cannonball and bullet test thing he did?).
No faster. Just more momentum.
It's that damn normal force that will get the lighter riders everytime.
and the heavy rider WILL ... take off
my science kung fu is too strong.
Mr Conundrum wrote:
people in glass houses wrote:Whats really going to blow his mind is heavier bikers have an advantge on flat terrain as well.
As to my way of thinking there should be no advantage and actually a disadvantage. Objects of different weights accellerate at from the force of gravity (in a free fall) at the same speed. Larger bodies create more wind resistance hence the larger body has a disadvantage.
Not sure though about the role of momentum in cyling as it relates to weight.
This question comes up often. The correct answer is that heavier cyclists *do* have an advantage going downhill.
The main thing that slows a rider going downhill is wind resistance. Wind resistance is proportional to cross sectional area. While wind resistance increases with rider weight, it does *not* increase linearly, because your body is three dimensional, and some of your increase in weight will be in increase in thickness from front to back. A rider who's 25% heavier will almost certainly not have 25% greater cross sectional area than the lighter rider. They will be thicker and wider. Thus, the net downhill force they experience will be greater, and they will accelerate faster than the lighter rider.
This also explains why larger riders have an advantage on relatively flat courses.
I agree that a heavier cyclist would have a slight advantage going down hill. Sure, gravity pulls on every atom just the same, but you need to compare the gravitational force to the drag force. The drag force is dependent on the frontal area of the rider and bike, which will not increase proportionately with the mass of the rider. Therefore, the heavier rider should see a lower drag force relative to his weight than the lighter rider, giving the heavier rider an advantage. The heavier rider will also have a greater rolling resistance from the wheels so this would negate some of the advantage, but not all of it.
Kele: correct.
Mass varies as the cube of linear dimension, frontal/resistance area as (roughly) the square.
Thank you, A Cyclist, for posting. I was thinking, Does any one not realize how much wind resistance slows a person on a bike? Obviously, a bunch of people who have never ridden a road bike posted on this thread.
The basic assumption here is that there is more gravitation acceleration for heavier objects. Hence (minus drag force or wind resistance factors) the heavier object goes goes faster downhill.
That is incorrect.
Mr Conundrum wrote:
The basic assumption here is that there is more gravitation acceleration for heavier objects. Hence (minus drag force or wind resistance factors) the heavier object goes goes faster downhill.
That is incorrect.
Correct:
http://www.youtube.com/watch?v=5C5_dOEyAfkNow, who will be the first to step up and tell us this video was shot in the Arizona desert?
Does a slab of wood and a piece of paper fall at the same rate? The real world is NOT a vacuum. Wind resistance matters!
Nothing falls at 9.8 m/s^2 on the earth's surface! An item of the same shape and size that is heavier will fall closer to 9.8 then a lighter one!!!!
I have a question wrote:
Does a slab of wood and a piece of paper fall at the same rate? The real world is NOT a vacuum. Wind resistance matters!
Nothing falls at 9.8 m/s^2 on the earth's surface! An item of the same shape and size that is heavier will fall closer to 9.8 then a lighter one!!!!
Read the post I replied to.
This is a basic ENERGY problem. Momentum will not be correct.
Of course, a heavier rider will have an advantage, unless they are shaped like a parachute. Now, the real question is how much heavier? A gram? A kilogram? Or 100 kilograms.
Height is equivalent to potential energy. You put energy into something simply by raising it up.
Drop a feather out of a plane, and it will take hours to hit the ground. Drop the same feather out of the plane, but with a 1 kilogram weight attached to it, and now it will take minutes. (depending on the height). It now has a larger effective surface area as well as worse aerodynamics, but that is overcome by the larger mass, thus more energy.
no peeps here wrote:
This is a basic ENERGY problem. Momentum will not be correct.
Of course, a heavier rider will have an advantage, unless they are shaped like a parachute. Now, the real question is how much heavier? A gram? A kilogram? Or 100 kilograms.
Height is equivalent to potential energy. You put energy into something simply by raising it up.
Drop a feather out of a plane, and it will take hours to hit the ground. Drop the same feather out of the plane, but with a 1 kilogram weight attached to it, and now it will take minutes. (depending on the height). It now has a larger effective surface area as well as worse aerodynamics, but that is overcome by the larger mass, thus more energy.
I'm not even going to touch this...