Adisc with radius r and mass m is free to rotate on a vertical plane about an axis through point a on its rim. assume there is no friction. initially the disc is held at rest so that the centre of the disc, g, is directly above a. the disc is then released. (a) calculate the moment of inertia of the disc for rotation about point a (b) determine the size of the angular velocity when ag is horizontal.

The ph is the a.independent variable b.the dependent variable c.control group

Which planet do you think would be easiest for humans to colonize some day?

Asled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slidesa distance d1 down the slope and then covers the distance d2 alongthe horizontal terrain before stopping. find the coefficient ofkinetic friction μk between the sled and the ground, assumingthat it is constant throughout the trip. find the coefficient of kinetic frictionμk. express your answer in terms of someor all of the variables d1, d2, and θ.