Answer
$$\left( {5,\frac{\pi }{2},1} \right)$$
Work Step by Step
$$\eqalign{
& {\text{We have the rectangular coordinates }}\left( {0,5,1} \right) \cr
& \left( {x,y,z} \right):{\text{ }}\left( {0,5,1} \right) \to x = 0,{\text{ }}y = 5,{\text{ }}z = 1 \cr
& {\text{Rectangular to cylindrical}} \cr
& {r^2} = {x^2} + {y^2} \to r = \sqrt {{{\left( 0 \right)}^2} + {{\left( 5 \right)}^2}} = 5 \cr
& \tan \theta = \frac{y}{x} \to \theta = {\tan ^{ - 1}}\left( {\frac{7}{0}} \right) = \frac{\pi }{2} \cr
& z = z \to z = 1 \cr
& {\text{The cylindrical coordinates are:}} \cr
& \left( {5,\frac{\pi }{2},1} \right) \cr} $$
