[填空题]
A 2.30-m-long pole is balant9jls( vke.13ksxqf(ced vertically on ;q4)l; zly3.hikdq xk its tip. It starts to fall and its lower end does not slip. What will be the speed of the upper end of the pole just before it hits the grounz;i k.q ;dk lx4y)3lqhd? [Hint: Use conservation of energy.] $m/s$
Post time 2025-2-18 20:00:22
