Centripetal Force and maximum speed

AI Thread Summary
To calculate the maximum speed of a motorcyclist approaching a hump-backed bridge with a radius of 14.4 m and a combined mass of 141 kg, one can apply the conservation of energy principle. At the top of the bridge, the kinetic energy is reduced due to the increase in potential energy, expressed as mgh = 0.5mv². The calculated maximum speed at which the rider can travel without leaving the road is 16.8 m/s. It is noted that the force keeping the motorcycle on the road is not friction. Overall, the discussion emphasizes using energy conservation to determine the maximum safe speed.
kingyof2thejring
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A motorcyclist is approaching a hump-backed bridge, as shown in the diagram. The bridge forms part of a circle of radius r = 14.4 m. The combined mass of the motorcycle and rider is 141 kg. Calculate the maximum speed in m s-1 at which the rider could travel without leaving the road at the top of the bridge.

How do i go about workin this one out without knowing Fmax and u\mu[\tex] coeff static friction. Thanks in advance
 
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If it's not given, I guess you get the pleasure of assuming that it is negligible.

Apply conservation of energy: kinetic energy will be less at the top of the hump.

Check if the velocity is less than which is required for circular motion.
 
What is the force keeping him on the road? It's not friction.

EDIT: Just seconds slower than mezarashi :smile:
 
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so mgh=0.5mv^2
and v=16.8
 
Päällikkö said:
What is the force keeping him on the road? It's not friction.

EDIT: Just seconds slower than mezarashi :smile:

Sorries! >.<
 
kingyof2thejring said:
so mgh=0.5mv^2
and v=16.8

You have the car coming at a certain velocity. Apply the conservation equation.

KE1 + PE1 = KE2 + PE2

The potential PE1 is zero, we consider ground. The potential at PE2 is mgh. We know KE1, find KE2. Use KE2 in your next step.
 
cheers mate mezarashi
its best to consider the moition using that equation
 
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