Rs
It’s spelt arse.
Ok, I’ve been lying awake all night trying to work this out.
When cycling in the rain with short mudguards.
How do the rain droplets (and grit) get from the wheel on to your back?
If you’re cycling at, say 20 kmh, the droplets are thrown from the tyre at that speed and immediately are subjected to gravity and a small amount of friction, which would slow them down. Meanwhile your back is also travelling at 20 kmh and should thus be out of reach of the droplets (and grit).
However, when you get home, you find a gritty wet stripe down the middle of the back of your jacket.
Explain that Boffins (or Bufons).
I’m no boffin on the subject, but I suppose there is a way to look at it that might offer some clues to the puzzle. Viz:
a) If you are travelling at 20kph, it makes sense to imagine, you, bike, back of your coat, mudguards, frame etc, are doing similar.
b) While you/bike/frame etc, are moving through the air at 20kph, other parts of the bike have additional movement, pedals, spokes, tyres for eg.
c) If the bike/frame/wheels are moving in a forward direction, lets say left to right, it also means, in this left to right movement, everything travels through the air/space at 20kph… including, the back of your coat.
d) Now if we consider the wheels are rotating, at the same time as the left to right movement is taking place, rotational speed of the wheels (rpm), taken at its largest diameter, or the outer tread of the tyres, we get what is called ‘tip speed’… obviously, this is different, and opposed to gear spindle speed.
e) In short, ‘tip speed’ will vary, depending upon the diameter of the wheel on the bike. For example, 21" 27" 29" will have differing metre per second ‘tip speed’, even if the RPM of its central spindle, is constant for each diameter.
f) Therefore, in travelling left to right at 20kph, the ‘tip speed’ of the outer diameter of the wheel (or tyre), will be travelling at a far greater speed, which enable the treads, or friction contact with the wet surface (roads), to be carried (scooped) up, and due to centrifugal forces, will fling anything attached to the tyres in an outward direction, faster than you are travelling… In this instance, your costly cycling jacket :0)
While I stand to be corrected on this, I hope this gives further food for thought..
Wonderful stuff!
Where’s Charlie?
sorry, no…
i am intrigued though
Clue: Became England Manager
ahhh…
jumped right out now…cheers
Mike Bassett?
Hoddle.
Is he the one sat down??..
There’s some really big heads in the photo so I’m going for Don Revie.
Bottom Right - Glen Hoddle when he was a whippersnapper
Ah, glad it was an actual thing. I thought I’d spotted Wally with the big glasses in the middle.
I did see that lad, but I wondered if it was David Icke back in his football days.