AP Physics U6

Krot

½ Iw²

Area under torque - theta curve is…

work done

W can equal..

change in KE rot

Area under sum of torque vs change in time graph is…

Equal to change in L (angular momentum)

L of system =

sum of L on all objects

Angular mom is conserved when…

no external torque is exerted

Angular speed of a non-rigid system may change w/o angular mom of system changing if…

the system changes shape by moving mass closer or further from rot. axis

When describing rolling w/o slipping system

use change in x = rtheta, v = rw, a = ra

Systems w increase in inertia rot have more KE ___ in their…

rotational, KE total

Angular mom of satellite and ME total is constant in…

circular + elliptical orbits

To find the escape velocity of an object from earth…

GPE must equal KE (1/2MV² = GMm/r)

L=mvr for…

coordinate system with object moving perp to radius, perpendicular line joins direction of v to x-axis

Object rolling down frictionless plane has no…

KE rotational

Rolling w slipping means…

• Kinetic friction acts on it

• Mechanical energy is lost as thermal

PE and KE is not constant in a satellite with an ___ orbit. It is constant with a ____ orbit.

elliptical, circular

Linear momentum of satellites in either orbit are…

not constant! direction constantly changes!!!!