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According to Bohr's theory, the angular momentum of an electron in 5th orbit is

1. 10 h/π
2. 2.5 h/π
3. 25 h/π
4. 1.0 h/π

Correct answer: 2.5 h/π

Solution

Bohr's theory states that the angular momentum of an electron in a given orbit is quantized and can be calculated using the formula L = nħ, where n is the principal quantum number and ħ is the reduced Planck's constant. For the 5th orbit (n=5), the angular momentum is 5ħ, which simplifies to 2.5 h/π when considering the appropriate conversion.

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