Mechanics > Rotational Dynamics > Angular Momentum Conservation DCS# ~1Q60.90 

INTRANSIGENT ROD


APPARATUS
rod with hole, ring, and string 202-15-E3


DESCRIPTION
A rod is suspended from its center and hangs at an angle of about 45° to the string.  If it is struck simultaneously on both ends in an attempt to give it the motion shown in figure 1, the rod will instead rotate as shown in figure 2, so that L remains constant.
intransigent rod
REFERENCE

S.A.A. Zaidi, “The Intransigent Rod,” Am. J. Phys. vol. 63, 855-857, (1995).