Physics · Atomic Spectra
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Velocity of electron moving in first orbit of hydrogen is:
- A
2.19 x 107 m/sec
- B
2.18 x 107 m/sec
- C
2.2 x 108 m/sec
- D
2.19 x 106 m/sec
The velocity of an electron in the first orbit of hydrogen can be calculated using the Bohr model formula:
v = n × h / (2π × m × r), where:
n is the principal quantum number (1 for the first orbit),
h is Planck's constant (6.63 × 10-34 Js),
m is the mass of the electron (9.1 × 10-31 kg),
r is the radius of the orbit (0.529 × 10-10 m).
Substituting these values gives a velocity of approximately 2.19 × 106 m/s. The other options are incorrect as they either exceed feasible values or are too high for the first orbit.
This value is too high for the velocity of an electron in the first orbit of hydrogen.
This value is also too high for the velocity of an electron in the first orbit of hydrogen.
This value exceeds the speed of light and is not possible for an electron.
This is the correct value for the velocity of an electron in the first orbit of hydrogen, based on Bohr's model.
Tagged under Physics · Atomic Spectra · 2010