Question

Consider the following mass distribution where the x- and y-coordinates are given in meters: 5.0 kg at (0.0, 0.0) m, 3.3 kg at (0.0, 3.5) m, and 4.0 kg at (2.9, 0.0) m. Where should a fourth object of 7.5 kg be placed so that the center of gravity of the four-object arrangement will be at (0.0, 0.0) m?

A 1.25 kg solid, uniform disk rolls without slipping across a level surface, translating at 4.00 m/s. If the disk's radius is 0.390 m, find the following.

(a) the disk's translational kinetic energy (in J)

(b) the disk's rotational kinetic energy

An old grindstone, used for sharpening tools, is a solid cylindrical wheel that can rotate about its central axle with negligible friction. The radius of the wheel is 0.330 m. A constant tangential force of 300 N applied to its edge causes the wheel to have an angular acceleration of 0.800 rad/s2.

(a) What is the moment of inertia of the wheel (in kg · m2)? kg · m2

(b) What is the mass (in kg) of the wheel? kg

(c) The wheel starts from rest and the tangential force remains constant over a time period of 5.50 s. What is the angular speed (in rad/s) of the wheel at the end of this time period?

Answer 1