Herexi=0.5quadomega_(d)=7540rad//sWe know that{:[omega_(d)=omega_(n)sqrt(1-xi^(2))],[:.quad7540=omega_(n)sqrt(1-0.5^(2))],[:.omega_(n)=8706.44rad//s],[:.quad phi(omega)=tan^(-1)((-2xi omega//omega_(n))/(1-(omega_(1)omega^(2)))],[=tan^(-1)((26.5^ ... See the full answer