Pros and Helmets

[screenman]

Really? You sure about that?

Maybe.

 

[doog]

Great thread.

Adrian has latched on as usual like an annoying little kid you want to pat on the head and send to bed. User13710 appears massively offended as per usual , regulator is regulating and saying nothing much and Cunobelin deals with the task in hand in the same old way (which i kind of like)

Then we have an expert thrown in and a few members of joe public( who are rounded on and vilified for even daring to post pro helmet) and of course Mike G, who like me when on his cycling journey through life happened upon a pitcher plant of a thread.

 

[Dan B]

Accelerating, not sure I get that one.

Gravity, dear boy. If you are vertically stationary at some distance above the earth with no means of support, then per Galileo, you will accelerate downwards towards it until such time something (such as the ground) interrupts your fall. This is independent of any horizontal velocity you might have, which is only going to make any difference to impact speed if (1) you hit something other than a purely horizontal surface, or (2) you pivot on something to transform that horizontal motion into vertical motion. It will contribute to road rash, though ;-)

 

[screenman]

So there you are sliding down the road from say 25mph but by chance your head does not touch until you have slowed to 12 mph. Hopefully at this point your head is still attached to your body.

 

[Fab Foodie]

So there you are sliding down the road from say 25mph but by chance your head does not touch until you have slowed to 12 mph. Hopefully at this point your head is still attached to your body.

..... And if it's not, what's the worry?

 

[screenman]

..... And if it's not, what's the worry?

one way to lose some weight I suppose.

 

[StuartG]

Hopefully at this point your head is still attached to your body.

I went to see "Bring up the Bodies" this week. It featured the execution of five folk by beheading which was done a little carelessly albeit greatly assisted by gravity. The issue was how to match up the heads and torsos for burial. Now if they had only been wearing matching helmets and lycra it would have been straightforward. See helmets can be really useful if you are about to receive a heavy head injury.

 

[noodle]

No. No, no, no..........This is where you're obviously struggling. Those two statements, despite your claim, are not in conflict. Let me say this again......

Medics are in a better position to comment as to whether or not a helmet may have helped in a particular accident, but not to give general advice as to the efficacy of helmets. Where on earth is the problem with that? It really is simple.....they've got a kid covered in grazes in front of them, and they can say.........."looks like the helmet saved him a head wound", but, (unless they have a special personal interest in cycling and have reviewed all the available research and data) they are in no position to say "all kids should be wearing a helmet".

i get it you are quite clearly stating that in this one instance a medical type is staiting they beleive hte helmet helped reduce the possible severity of the incident
the same medic is not saying everyone should wear a helmet as it will always reduce the severity of any given incident

and im typing with one eye closed so the screen is in normal vision not wobbly double
i do get the feeling some people like to argue and fail

 

[noodle]

acceleration could be caused by rotational forces eg knees hhit first and hit whips your head round leading to an increased impact speed fo rthe head as opposed to the knees

i think overall taking a fairly broad average no acceleration occurs, if your working with two terms for it those being acc and deceleration. if you just stick with acceleration as lets face it it is acceleration in whichever way you look then it always occurs

 

[noodle]

Gravity, dear boy. If you are vertically stationary at some distance above the earth with no means of support, then per Galileo, you will accelerate downwards towards it until such time something (such as the ground) interrupts your fall. This is independent of any horizontal velocity you might have, which is only going to make any difference to impact speed if (1) you hit something other than a purely horizontal surface, or (2) you pivot on something to transform that horizontal motion into vertical motion. It will contribute to road rash, though ;-)

missing terminal velocity and a rather inconvenient thing gallileo didnt see coming, newtons gravitation works better anyway

been abroad of late, horizontal velocity can and does overcome gravity takes a fair bit of brute force mind

 

[noodle]

worms can
ive wrote two helmets off now

first a bell full face bit of a big hit i still have the bent bits after being out for it for a few moments ive sat up took the goggles off as i couldnt see out of them (blood from nose) and unbuckled the helmet which when dropped to the floor fell apart (no idea on any of this i was told this afterwards) what i do know is i have one bent tooth and a fair bit of scar tissue on the inside of my mouth some on my arm where a bit of twig punctured it
did that helmet help quite probably yes i would say it did as did the dianese armour im still walking and talking and able to enjoy these adnams
second on my way home form work around 05 ive come round a corner into a willow that had been 'swung' on so it was a lot lower than it had been going into work, helmet caught something by a tiny margin and pulled my head back and me of the bike
did the helmet help then obviously no and if any paramedic tried telling me it had i would have been rather rude to them

do i think a bit of poly will save me if a car hits me well mostly no unless im lucky enough to be hit just right, could it save me?
ill wear one just in case lets face it if a tyre goes on me a 10mph and i get pitched head first onto the floor then not having one on is not going to help is it.
yes in some instances they can work against you just as airbags do in cars
question for everyone have you swicthed yours off?

 

[Dan B]

missing terminal velocity and a rather inconvenient thing gallileo didnt see coming, newtons gravitation works better anyway

been abroad of late, horizontal velocity can and does overcome gravity takes a fair bit of brute force mind

I have no idea what you're talking about. How is terminal velocity relevant and what is this inconvenient thing? Or is terminal velocity the inconvenient thing? I think you'd have to be riding a very tall bike indeedd for air resistance to markedly affect your speed on the way to the ground

 

[noodle]

I have no idea what you're talking about. How is terminal velocity relevant and what is this inconvenient thing? Or is terminal velocity the inconvenient thing? I think you'd have to be riding a very tall bike indeedd for air resistance to markedly affect your speed on the way to the ground

Can't even remember posting that so hey ho
But I'm guessing I was being a bit of a pedant over the acceleration thing as it doesn't continue apace nor is it the nice figure oft quoted by most none physicists as figures like that are only relevant in a vacuum which we are not riding in
Planes have no means of support and the whole lift by wings isn't quite right

 

[noodle]

I always knew this but people just dismissed it as irrational fear. Turns out I was right all along.

I always knew this but people just dismissed it as irrational fear. Turns out I was right all along.

Nope they really shouldn't be up there at all