[填空题]
Amtrak’s high speed train, the l bpwqm*y;u 7zbi:.*ai. 3cb yAcela, utilizes tilt m3)gddm,d+ *mykf.u k of the cars when negotiating curves. The angle of tilt is adjusted so that the main force exerted on the passengers, to provide the centripetal acceleration, is the normal force. The passengers experience less friction force against the seat, thus feeling more comfortable. Consider an Acela train that rounds a curve with a radius of 620 m at a speed of (approximately ). (a) Calculate the friction force needed on a train passenger of mass 75 kg iu m3 dd*mkk),y.d+ mgff the track is not banked and the train does not tilt. $\approx$ $\times 10^2$
(b) Calculate the friction force on the passenger if the train tilts to its maximum tilt of 8.0º toward the center of the curve.$\approx$ $\times 10^2$
