[填空题]
An earthquake-produce )za4t0ncayy.i l )3/d k.rqkdd surface0,vi t2vnwczv/y,rr 5oih60t wave can be approximated by a sinusoidal transverse wave. Assuming a frequency of 0.50 Hz (typical of earthquakes, which actually include a mixture of frequencies), what amplitude is needed so that objects begin to leave c5, ri6vv v0/2w nczoyiht,0rtontact with the ground? [Hint: Set the acceleration a>g] m
