UID:3665
UID:355
游堪琼:1、对卡车做受力分析、卡车受重力、支持力、 ld7B!_b< 则由牛顿第三定律 ld7B!_b< P=F/S=G/S=32000/0.5=64000(Pa) ld7B!_b< 2、 ld7B!_b< W=Gh=W η=Fsη s=2h ld7B!_b< ....... (2012-05-03 20:23) ld7B!_b<
UID:6452
UID:3922
UID:3623
UID:6660
UID:6925
UID:6506