Old Tech thread

dask

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Pyan

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I would have thought that the pivot point of the needle should be in the centre of the bus, not to one side. I can't see the point of it being where it is.

Perhaps it doesn't make any difference?
I would have thought that the angle would be constant no matter where the pivot point was, but...

Have we any mathematicians among us?
 

mosaix

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I would have thought that the angle would be constant no matter where the pivot point was, but...

Have we any mathematicians among us?
I agree that the angle would be constant* but wasn't the idea of the needle to show where the centre of gravity lies and if it falls outside the base of the bus?

The strange thing is that the two needles show different readings.

*Edit - I'm not sure about that now.
 

Pyan

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Ah, I thought it was just an indicator against the quadrant scale, and not relevant to any point on the actual bus.
 

Pyan

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The strange thing is that the two needles show different readings.

The difference is is the take-up of the bus's suspension. The one on the left shows the platform angle, but the one on the bus shows the actual angle of the bus - which isn't perpendicular to the platform.
 

mosaix

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Ah, I thought it was just an indicator against the quadrant scale, and not relevant to any point on the actual bus.
The bias in my reasoning is that, at secondary school, we had a physics textbook with a practically identical picture on the front showing a leaning bus with needle. It was at an extraordinary angle but didn't fall over as the needle was pointing within the base of the bus - unlike the photo.
 

Astro Pen

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The difference is from the suspension springs. And I guess a difference outside norms would reveal weakening suspension.
 

Dave

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If I was in a bus travelling at that angle, I think I'd be un unbalanced passenger whichever floor I was on (and despite my unhealthy weight).
If I was a bus driver and the road had that kind of camber then I'd be worried too. I'd probably be experiencing some landslip, earthquake or other geological event.
 

Christine Wheelwright

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The ability of double decker busses to stay upright as they go around corners is one of the great miracles of physics. Especially because you could have 20+ people upstairs and nobody downstairs.
 

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