Consider a turntable to be a circular disk of moment of inertia it rotating at a constant angular velocity ωi around an axis through the center and perpendicular to the plane of the disk (the disk's "primary axis of symmetry"). the axis of the disk is vertical and the disk is supported by frictionless bearings. the motor of the turntable is off, so there is no external torque being applied to the axis. another disk (a record) is dropped onto the first such that it lands coaxially (the axes coincide). the moment of inertia of the record is ir. the initial angular velocity of the second disk is zero. there is friction between the two disks. after this "rotational collision," the disks will eventually rotate with the same angular velocity.

Under conditions for which the same room temperature is maintained by a heating or cooling system, it is not uncommon for a person to feel chilled in the winter but comfortable in the summer. provide a plausible explanation for this situation (with supporting calculations) by considering a room whose air temperature is maintained at 20â°c throughout the year, while the walls of the room are nominally at 27â°c and 14â°c in the summer and winter, respectively. the exposed surface of a person in the room may be assumed to be at a temperature of 32â°c throughout the year and to have an emissivity of 0.90. the coefficient associated with heat transfer by natural convection between the person and the room air is approximately 2 w/m2 â‹…â‹… k. what is the ratio of the thermal resistance due to convection to the thermal resistance due to radiation in the summer? what is the ratio of thermal resistances in the winter

Aball has an initial velocity of 3 m/s. if there is no friction, what is the highest it could roll?

One form of energy can be another type of energy. a. created to form b. transformed into c. destroyed and then created to form