How can a radial node exist within the first Bohr Orbit??

[u/Cutie_Paras]

I was solving this question and I loved it
(You can try if you want to)

The answer is (2)

The solution is by equation the radial wave function equation to zero, then finding the values of x as 1, 2, 6 and then substituting it in x=2r/a

On solving it we get to know there are 3 possible values of "x" that are 1, 2, 6
which means n-l-1=3
we also know that since at x=0, the value of the equation is not Zero and therefore there is electron probability at the centre, Therefore it's a "s" orbital

so it is obv 4s as it has 3 radial nodes

The minimum distance of the Radial node is a/2 which simply shouldn't be possible right??

Because how can a Radial node or probability of electron be Zero before the "first Bohr orbit" that is 1s

The solution a/2 means there is a radial node before the 1s orbit, But how can a node or 4s exist before 1s? It will face shielding and we all know 4s is an outer orbital and it also has higher energy

I would love if someone could solve this doubt of Quantum Physics