Two people on top of a hill?
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Two people on top of a hill?
Okay you have two people on top of a hill on identical bikes. One person weights 100 lbs while the other weights 200 lbs. If all things were equal and they costed down the hill would they both go the same speed?
If they both exerted the same amount of energy would they go the same speed?
Why is it when I am going down hill with my 200 lbs it appears I am going faster than everyone else?
If they both exerted the same amount of energy would they go the same speed?
Why is it when I am going down hill with my 200 lbs it appears I am going faster than everyone else?
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Because you are. It's called physics. This question has been discussed here a thousand times...well almost. The knowledgeable get it. The others don't.
Simply put if your size and shape were the same as the lighter rider, you would both descend at the same speed. But your net acceleration (gravity minus aero drag deceleration) is greater than his because you get your weight at a frontal area discount.
Simply put if your size and shape were the same as the lighter rider, you would both descend at the same speed. But your net acceleration (gravity minus aero drag deceleration) is greater than his because you get your weight at a frontal area discount.
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Don't get so excited. We run the dishwasher every day too. And wash clothes several times a week.
You keep garbage in the house overnight? Eeew!
You keep garbage in the house overnight? Eeew!
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Okay you have two people on top of a hill on identical bikes. One person weights 100 lbs while the other weights 200 lbs. If all things were equal and they costed down the hill would they both go the same speed?
If they both exerted the same amount of energy would they go the same speed?
Why is it when I am going down hill with my 200 lbs it appears I am going faster than everyone else?
If they both exerted the same amount of energy would they go the same speed?
Why is it when I am going down hill with my 200 lbs it appears I am going faster than everyone else?
#12
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Okay you have two people on top of a hill on identical bikes. One person weights 100 lbs while the other weights 200 lbs. If all things were equal and they costed down the hill would they both go the same speed?
If they both exerted the same amount of energy would they go the same speed?
Why is it when I am going down hill with my 200 lbs it appears I am going faster than everyone else?
If they both exerted the same amount of energy would they go the same speed?
Why is it when I am going down hill with my 200 lbs it appears I am going faster than everyone else?
The heavier person will likely go much faster
F (force) = m (mass) x a (acceleration)
a = F / m
Going downhill: F (force) = m (mass) x g (gravity) - Wind Resistance
Downhill Acceleration a (m/sec2) = g - Wind Resistance/ mass
Assume At the same speed, same aerodynamic position and same bike, roughly, Wind Resistance is proportional to surface area. The 200 lb rider is unlikely to have twice as much surface as the 100 lb rider. If both riders have exactly the same built, the surface area of the 200 lb rider is theoretically (200/100)^(2/3) - 100% =~60% more than the 100 lb rider.
In short, at the same speed, even though the gravity (g) is same, the light rider is being penalized a lot more by wind resistance.
In reality, as the speed of the heavier rider increases, the wind resistance increases even more (Resistance is proportional to ~(Velocity)^2)
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Because you are. It's called physics. This question has been discussed here a thousand times...well almost. The knowledgeable get it. The others don't.
Simply put if your size and shape were the same as the lighter rider, you would both descend at the same speed. But your net acceleration (gravity minus aero drag deceleration) is greater than his because you get your weight at a frontal area discount.
Simply put if your size and shape were the same as the lighter rider, you would both descend at the same speed. But your net acceleration (gravity minus aero drag deceleration) is greater than his because you get your weight at a frontal area discount.
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Okay you have two people on top of a hill on identical bikes. One person weights 100 lbs while the other weights 200 lbs. If all things were equal and they costed down the hill would they both go the same speed?
If they both exerted the same amount of energy would they go the same speed?
Why is it when I am going down hill with my 200 lbs it appears I am going faster than everyone else?
If they both exerted the same amount of energy would they go the same speed?
Why is it when I am going down hill with my 200 lbs it appears I am going faster than everyone else?
Wait, they are exerting energy? If it was the "same amount of energy" and it was enough to offset the gravity benefit of the heavier rider, (seems it wouldn't be difficult to do this) then wouldn't the lighter rider win?
#24
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Gravity (g = 9.81 m/sec2) is really the same for heavier and lighter riders. At high speed descent, lighter riders tend to experience a higher wind resistance (per unit weight). As a result, "net acceleration" going downhills (gravity - impact of wind resistance per unit weight) favors the heavier riders.
#25
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E = mv^2/2 + mgh
More 'm' makes for more 'E', all else equal, and given that, more 'E' makes for more 'v'.
More 'm' makes for more 'E', all else equal, and given that, more 'E' makes for more 'v'.