Recent content by HoloBarre

Homework Statement A stick of mass M, length L, stands upright on a table, pivoted to the table. What is the angular velocity as it hits the table? Homework Equations ang. accel = (3g/2L)cos theta w = (3g/2L) integral cos theta dt The Attempt at a Solution theta (t) = ...

Homework Statement A stick of mass M, length L is standing upright on a table, pivoted at the bottom. What is its angular velocity as it hits the table? Homework Equations ang. accel = (3g/2L)cos theta (theta is zero with stick laying on table) The Attempt at a Solution...

All -- With a meter stick standing straight up and pivoted at the *bottom*, what is the final angular velocity as it hits the table? I've found plenty of standard stuff on physical pendulums (meter stick pendulum), where I = 1/12 MR^2, period, etc, but I can't find velocity info...

I have asserted that Newton's Cradle does not demonstrate specifically that P = mv or that E = 1/2mv^2. Rather, that it demonstrates only that two *different* laws of motion/conservation are simultaneously at work. An alternative form of this assertion is that by observing Newton's...

re Russ Watters: An air conditioner IS a heat pump -- just turn it around in the window! iiuc, modern combination A/Cs-heat pumps (Mitsubishi's/Fujitsu's, etc) don't mechanically switch air flows, they re-route the refrigerant through different coils, or some such thing. To the OP, when you...

I think part of the problem is that energy/momentum/collision equations say little or nothing about forces themselves, but only as a force in integrals of Fdt and Fdx. Thus, F by itself is poorly constrained. However, by making dx, dt, and V all essentially zero, maybe now somehow F is...

A weird collision "theorem" All -- Many moons ago I thought I heard a professor refer to a "theorem" in mechanics which stated that if a hard object is released from an infinitesimal height above a hard surface, the force will be exactly twice the weight of the object. Did I hear...