Which subatomic particle has a positive charge? a) electron b) neutron c) nucleus d) proton

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At 20∘c, the hole in an aluminum ring is 2.800 cm in diameter. you need to slip this ring over a steel shaft that has a room-temperature diameter of 2.804 cm . 1. to what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? coefficients of linear thermal expansion of steel and aluminum are 12×10−6 k−1 and23×10−6 k−1 respectively.

What is the moment of inertia i of this assembly about the axis through which it is pivoted? express the moment of inertia in terms of mr