[问答题]
A person stands, hands at his side, on -rl50moqw/nuc jvtr4s(90qra platform that is r6 m,jy8o*nkc fro-y0 totating at a rate of 1.3rev/s If he raises his arms to a horizontal position, Fig. 8–48, theymo-06n*f to,j 8yr kc speed of rotation decreases to 0.8 $rev/s$ (a) Why? (b) By what factor has his moment of inertia changed?
Post time 2025-2-18 20:00:22
