Any municipality proceeding to acquire, construct, own, lease or operate a public utility, or to contract with any person or company therefore, shall act by ordinance and no such ordinance shall take effect until after thirty days from its passage. If within said thirty days a petition signed by ten per centum of the electors of the municipality shall be filed with the executive authority thereof demanding a referendum on such ordinance it shall not take effect until submitted to the electors and approved by a majority of those voting thereon. The submission of any such question shall be governed by all the provisions of section 8 of this article as to the submission of the question of choosing a charter commission.