Why Speed Limit for Vehicle Skidding Independent of Mass

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The discussion centers on why the speed limit for vehicles skidding is independent of mass, emphasizing that factors like weight distribution, tire quality, and road conditions play significant roles. While mass affects frictional force, it cancels out in the equations governing kinetic energy and friction when analyzing skidding. Lorries are subject to lower speed limits primarily due to their longer stopping distances, not necessarily because of their mass. The conversation highlights the complexities of vehicle dynamics and the importance of various factors beyond just mass. Understanding these principles is crucial for addressing urgent vehicular motion questions.
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Skidding problem [Urgent]

Why the limiting speed of the venhicle without skidding is independent of its mass?

For example, why lorries may have to go at a slower speed than the 25m/s
limit for cars

But why this does't depend on the mass but the speed:confused:
 
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It's dependent upon a lot of things, not the least of which is mass. Other factors include weight distribution, tire compounds and quality, road surface conditions, etc.. I'll leave the details for others more versed in the matter.
 
andrew...if you have studied rotational motion and the parallel axis theorem then here is how it goes...snece the vehicle is rolling...the total kinectic energy possesed by it is .5mv^2+.5Iw^2...were i is the rotational inertia and w is rotational spped...since the i for wheels is .25mr^2..think u so...then..we can eqaute this to the firctional energy...which is equivalent to the friction force times the distance travelled...u know that frictional force is dependent on the mass of vehicle...hce...if we would equate these variable...mass would get canceled of!...
 
I love these "urgent" vehicular motion questions.

I imagine andrew furiously typing away on his laptop in the car. "Urgent! What is the braking distance on a 97 Chevy?"
Followed 20 seconds later by "Never mind..."
 
A lorry has a lower speed limit simply because it takes longer to stop normally. ( it probably stops just as quickly as any other vehicle if it hits a wall though... almost)
 
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Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
I was thinking using 2 purple mattress samples, and taping them together, I do want other ideas though, the main guidelines are; Must have a volume LESS than 1600 cubic centimeters, and CAN'T exceed 25 cm in ANY direction. Must be LESS than 1 kg. NO parachutes. NO glue or Tape can touch the egg. MUST be able to take egg out in less than 1 minute. Grade A large eggs will be used.
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