JSFiddle - React, Tailwind, and code Playground
HTML
<input type="radio" id="r1" checked/>
<input type="radio" id="r2"/>
JavaScript
alert($("#r1").attr("checked"));
alert($("#r2").attr("checked"));
<input type="radio" id="r1" checked/>
<input type="radio" id="r2"/>
alert($("#r1").attr("checked"));
alert($("#r2").attr("checked"));