Formulas for calculations of the first natural frequency of vibration for columns in a form of frustum of cone and tubes shaped like a cone are derived. Elastic material and continuous distribution of the column mass was assumed. Rayleigh’s method was used and the form of amplitude of cone axis during the vibration was supposed to be described by a trigonometric function. The application of derived formulas was presented using some examples and results obtained are compared with those given in other papers and calculated according to Polish standard PN-77/B-02011.

37-50