A metal hoop of mass 2.5 kg and with a radius of 0.5 m rolls smoothly without sl
ID: 2209454 • Letter: A
Question
A metal hoop of mass 2.5 kg and with a radius of 0.5 m rolls smoothly without slipping along a floor with a velocity of 2 m/s. It then encounters a ramp and rolls up the ramp to some maximum height before stopping. (a) After consulting the formula sheet provided with this exam write down the relevant formula for the rotational moment of inertia of this metal hoop. (b) While it is rolling horizontally, before encountering the ramp, what is the total kinetic energy of the metal hoop? (c) What is the maximum vertical height reached by the hoop on the ramp before it stops?Explanation / Answer
KE for linear motion is .5 m v^2; for rotational motion KE .5 I W^2 where I = mom of inertia W = angular velocity radians / sec. in 2 put I = 4.06 and W = 1 rev = 2 pi() radians / 3.36 sec = 1.87 and solve In 1 you need to add linear motion KE and Circular motion KE but same equations apply.