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1 year ago

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Using the formula for kinetic energy of a moving particle k=12mv2, find the kinetic energy ka of particle a and the kinetic ener

gy kb of particle
b. remember that both particles rotate about the y axis.

1 answer:

Flauer [41]1 year ago

5 0

<span>Answer: KE = (11/2)mĎ‰Â˛rÂ˛, particle B must have mass of 2m, while A has mass m. Then the moment of inertia of the system is I = ÎŁ mdÂ˛ = m*(3r)Â˛ + 2m*rÂ˛ = 11mrÂ˛ and then KE = Â˝IĎ‰Â˛ = Â˝ * 11mrÂ˛ * Ď‰Â˛ = 11mrÂ˛Ď‰Â˛ / 2 So I'll proceed under that assumption. For particle A, translational KEa = Â˝mvÂ˛ but v = Ď‰*d = Ď‰*3r, so KEa = Â˝m(3Ď‰r)Â˛ = (9/2)mĎ‰Â˛rÂ˛ For particld B, translational KEb = Â˝(2m)vÂ˛ but v = Ď‰*r, so KEb = Â˝(2m)Ď‰Â˛rÂ˛ so total translational KE = (9/2 + 2/2)mĎ‰Â˛rÂ˛ = 11mĎ‰Â˛rÂ˛ / 2 which is equal to our rotational KE.</span>

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