Atomic StructureHard
Question
A electron in the hydrogen atom jumped from excited state n to the ground state. The wavelength so emitted illuminates a photosensitive material having work function 2.75 eV. If the stopping potential of the photoelectron is 10 V, then the value of n is
Options
A.2
B.3
C.4
D.5
Solution
Here, stopping potential, V0 = 10V
Work function, W = 2.75 eV
According to Einstein′s photoelectric equation
or
= 10 eV + 2.75 eV = 12.75 eV ...... (i)
When an electron in the hydrogen atom makes a transition from excited state n to the ground state (n = 1), then he frequency (
) of the emitted photon is given by
h = En - E1
h = - 
[∵ For hydrogen atom, En =
]
According to the given problem
+ 13.6 = 12.75 [Using (i)]
= 0.85 ⇒ n2 = 
or n = 4
Work function, W = 2.75 eV
According to Einstein′s photoelectric equation
or
= 10 eV + 2.75 eV = 12.75 eV ...... (i)
When an electron in the hydrogen atom makes a transition from excited state n to the ground state (n = 1), then he frequency (
) of the emitted photon is given by h
= En - E1h
= - [∵ For hydrogen atom, En =
]According to the given problem
+ 13.6 = 12.75 [Using (i)] = 0.85 ⇒ n2 = or n = 4
Create a free account to view solution
View Solution FreeMore Atomic Structure Questions
A car is moving horizontally with a velocity v. A shell is fired upward with velocity u from the car. Find the horizonta...In an n-p-n transistor circuit, the collector current is 10 mA. If 90 % of the electrons emitted reach the collector...the ratio of kinetic energy to the total energy of an electron in a Bohr orbit of the hydrogen atom, is :-...Two identical p-n junctions may be connected in series with a battery in three ways. The potential drops across the two ...When 5V potential difference is applied across a wire of length 0.1 m, the drift speed of electrons is 2.5 × 10-4 m...