In that exact case yes, but I like to operate on the assumption that my trailer brakes are permanently broken. I’ve had them fail to operate mid-trip because they’re fucking trailer brakes.
Fn is proportional to the mass of the trailer, so it is irrelevant for the deceleration (a) if it is empty or not (because Ff = m*a).
µ is a constant relying on the tire/ground connection. Comparable to the towing car (if you happen to have car tire quality ones on your trailer, which might be doubtful)
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On top of that, typical car trailers use overrun brakes that per definition work by exerting an additional force on the towing vehicle in the direction of movement that is then used to activate the trailer brake.
Fair enough, car trailers do have garbage braking most of the time anyway. I may be biased because locomotives are so heavy and the traction you get with steel is shit so they actually benefit from some load behind…
I meant tailgaiting with your train ;-)
(but yes, I am aware of the systems that prevent that, heard some interesting talks about the topic and seen demonstrations in our local railway museum)
That is an oversimplified friction model that does not apply well to emergency braking. I still don’t think you get a better braking distance with a trailer in a typical situation but thats not the reason why.
If the trailer has very good brakes set to full power even when nearly empty, it’s actually true, but I doubt that’s the case…
I actually asked him that at the time
Glad you’re alive then.
Afterwards, had a quiet word to my spouse:
In that exact case yes, but I like to operate on the assumption that my trailer brakes are permanently broken. I’ve had them fail to operate mid-trip because they’re fucking trailer brakes.
I am pretty sure physics says “no”:
Ff <= µ*Fn
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On top of that, typical car trailers use overrun brakes that per definition work by exerting an additional force on the towing vehicle in the direction of movement that is then used to activate the trailer brake.
Fair enough, car trailers do have garbage braking most of the time anyway. I may be biased because locomotives are so heavy and the traction you get with steel is shit so they actually benefit from some load behind…
Locomotives? What is your profession?
In any case, I seriously hope that you are not tailgaiting ;-)
Freight train driver. I don’t tailgate, I like to leave plenty of distance in front of my car.
I meant tailgaiting with your train ;-)
(but yes, I am aware of the systems that prevent that, heard some interesting talks about the topic and seen demonstrations in our local railway museum)
That is an oversimplified friction model that does not apply well to emergency braking. I still don’t think you get a better braking distance with a trailer in a typical situation but thats not the reason why.