Accident on London Bridge

[Blackandblue]

From that picture, there is no way of telling what distance the motorbike travelled before it settled on its final resting place, or what impact it may have had at what speed with other objects which may have caused it to stop travelling any further than where it finally rested.

Unless we were there and saw what happened, none of us can do anything other than speculate.

 

[Lurker]

Although not relevant to this accident, from what I've read about it... don't forget a head on 30mph crash has the net result of 60mph into a brick wall.

Surely not.... the kinetic energy of a head-on 30mph crash is very different from a 60mph crash into a brick wall - not that either appeals.

Assuming a 1-tonne vehicle (average car) in each case, the kinetic energy works out as:

30mph head-on crash
vehicle 1 - 1/2 x 1 tonne x 30mph x 30mph = 450
vehicle 2 - 1/2 x 1 tonne x 30mph x 30mph = 450

Total KE = 450 + 450 = 900


60mph crash into brick wall
vehicle KE = 1/2 x 1 tonne x 60mph x 60mph = 1800

 

[SavageHoutkop]

valid point there... I was just running off speed differential.
You've now got me doing some quick calculations myself -

if a 100kg bike+cyclist are pedalling along at 10mph, 1,000 Joules of energy (a quick wikipedia shows that you need speed in m.s and weight in kg for it to be Joules coming out the other end...)

if a 1000kg bus is driving along at 30mph, 178,000 Joules.

Net Joules if head on - 179,000 Joules.

Equivalent speed for a cyclist to get to that many Joules by hitting a brick wall...

134 mph.

 

[Will1985]

I get lost with all the calculations, but Linf's guesstimation of 10-15m looks right to me.

Just as another perspective - on my crash in January where I went over a bonnet at 26mph, I ended up approximately 8m beyond the car with the bike somewhere inbetween having disconnected the cleats in the somersault. I assume the calculations above show that something heavier would travel further at the same speed. Presumably the type of collision would affect this too?

 

[Brains]

The Police now have a yellow board out, seeking witnesses to a "serious accident involving a motorcycle"

Anyone know what happened to the motorcyclist ??

 

[hackbike 666]

Yeah that's been up all week.

 

[mr_cellophane]

The Police now have a yellow board out, seeking witnesses to a "serious accident involving a motorcycle"

Anyone know what happened to the motorcyclist ??

He works on the same office as me. He is in a coma. Not sure if it is induced or as a direct result of the accident.

 

[hackbike 666]

Hope he pulls through.