Calculate the ratio of the radius of `1^(st)` orbit of H atom to thatof`4^(th)`orbit.
Hint `: r_(n) prop ( n)^(2)`

Explanation

To calculate the ratio of the radius of the first orbit of a hydrogen atom to that of the fourth orbit, we can use the formula for the radius of a Bohr orbit, which is given by:

\[ r_n \propto n^2 \]

where \( n \) is the principal quantum number (the orbit number).

### Step-by-Step Solution:

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