Rotational Motion, Rolling Motion

AI Thread Summary
The discussion revolves around a physics problem involving a motorcycle's motion as it ascends a hill. The key concept used to solve the problem is the Conservation of Energy, represented by the equation Mgh = 1/2 Mv^2 + 1/2 Iω^2 + 1/2 Iω^2. The confusion arises regarding the last two terms, which represent the rotational kinetic energy of the motorcycle's two wheels. It is clarified that there are indeed two terms because there are two wheels contributing to the total rotational inertia. Understanding this aspect is crucial for accurately applying the Conservation of Energy principle in this scenario.
mateomy
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Im looking over an example that was given in class that I jotted down in my notes; the question posed was...A 320 kg motorcycle includes two wheels each of which is 52 cm in diameter and has rotational inertia 2.1 kg*m^2. The cycle and its 75 kg rider are coasting at 85km/hr on a flat road when they encounter a hill. If the cycle rolls up the hill with no applied power and no significant internal friction, what vertical height will it reach?


So anyway...professor used the Conservation of Energy...

<br /> Mgh= \frac{1}{2}Mv^2 + \frac{1}{2}I\omega^2 + \frac{1}{2}I\omega^2<br />

Im just confused on the last two terms. Is there 2 of them because of the two wheels?
 
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mateomy said:
Im just confused on the last two terms. Is there 2 of them because of the two wheels?

Yes.

ehild
 
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