Total pressure load on a chain...

Scenario- I'm riding a bike up a mountain road, at a constant speed of 5 mph, at a constant grade of 11%. The bike plus me (and all gear) weighs in at 200 pounds.

Based on this (and excluding frictional losses, wind, etc.) how much TOTAL pressure, in pounds is on the chain? Would it be WxG (200*.11) for a result of 22 pounds? Yea? No?

I know this is basic.....but I want to be sure I've not overlooked something and thus will take myself on a tangent. Wouldn't be the first time.
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hi maximiliano!
 Quote by maximiliano Scenario- I'm riding a bike up a mountain road, at a constant speed of 5 mph, at a constant grade of 11%. … (and excluding frictional losses, wind, etc.) how much TOTAL pressure, in pounds is on the chain?
it's not pressure, it's tension, and that's a force (measured in pounds)

it depends on the gearing

from the work energy theorem, the rate of work done equals the rate of change of (mechanical) energy

at constant speed, and excluding friction etc, the energy is just weight (W) times height

so the rate of change of energy is W times height-per-second, = w times speed times sin11° (∆KE = Wvsinθ)

work done = force times distance, so rate of work done = force times speed (of the thing doing the force),

so force = rate of work done / speed of the chain

= Wvsinθ / speed of the chain

= Wsinθ times (speed-of-bike)/(speed-of-chain)

(similarly, the force you apply to the pedals is Wsinθ times (speed-of-bike)/(speed-of-pedals))
 Thanks Tim. Yes, but I'm ONLY looking for the calculation of the tension on the chain. Work done doesn't interest me one bit, and that's why I intentionally excluded any mention of time. I was just taking the weight being moved multiplied by the grade/slope of travel. I used a VERY slow speed intentionally as well, because I don't want there to be any additional tension (of any significant amount anyway) added to the equation. Gravity is the only constant force I wanted there. So.....it's 200 pounds moving at a slow and perfectly constant rate of speed up a road of 11% slope. The tension on the chain, in pounds, would be 200*.11? Or is the calculation not linear like that?

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