Pulling a truck (maths physics question)

[Ming the Merciless]

Yes, it is possible. Start off near the top of a hill and face downwards.

 

[swansonj]

If we're going to look at this simplisitcally,

Energy = Force X Distance

In terms of power:

Power = Force X velocity

The force needed to overcome the rolling resistance of the truck tyres is (from your figures) 2590 N.
Velocity = 0.17 mph or 0.076 m/s

required power = 2590 X 0.076 = 196 W
Not very much, but not that surprising: they used to tow fully laden barges along canals with one person or one pony - and drag from the water is significant, even at fairly low speeds.

There's one small drawback. In order to generate the needed 2590 N force, the driving tyre of must be able to exert 2590 N against the ground. It has to be loaded with at least 264 kg in order to do so, otherwise it'll just skid. You cannot ignore the reaction forces acting on the tyre. So if you ensure that the rear wheel is weighed down at least 264 kg it would be possible to exert sufficient force as long as the gear ratio is large enough. Except... you can't ignore stiction, either. That increases the forces required several fold, at least.

The ballast issue is even worse than that. You want the tow rope attached as low as possible to the ground, but however low it is, it still exerts an overturning moment. In theory you could balance the bike on rear wheel only - in slightly less theory, you need some weight on the front wheel keep it on the ground to steer it (yeah, at 0.1 mph..)

Ideally you want to convert some of the tension in the towrope into downforce, which requires the bike to be on an elevated track with the two rope sloping up.

 

[marinyork]

For these sorts of problems, the first thing I would think of is a realistic calculation for the coefficient of friction when the truck is stationary. The coefficient of friction generally changes between once it is moving and at rest and many textbooks from A-level onwards make the general distinction.

things like that.

 

[machew]

View attachment 371484

There is a fair bit of bend on Geoff's cog

 

[Beebo]

There is a fair bit of bend on Geoff's cog

His bottom bracket looks shot to me.
But he must be laying down a fair bit of power.