Tests carried out with the tilting trains described in Prob. 12.54 revealed that passenger...

Tests carried out with the tilting trains described in Prob. 12.54 revealed that passengers feel queasy when they see through the car window s that the train is rounding a curve at high speed, yet do not feel any side force. Designers, therefore, prefer to reduce, but not eliminate that force. For the train of Prob. 12.54, determine the required angle of tilt ϕ if passengers are to feel side forces equal to 12 percent of their weights.

Fig. P12.55