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प्रश्न
Use Einstein’s photoelectric equation to show how from this graph,
(i) Threshold frequency, and (ii) Planck’s constant can be determined.
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उत्तर
eV0 =hυ - hυ0
`V_0 = h/e(υ - v_0)`
Point A on the graph shows threshold frequency.
eV0 = hv - Φ0
`V_0 = h/e υ - (phi _0)/e`
Slope of the given graphs gives `h/e`
Slope `= h/e`
h = e × slope of the graph
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संबंधित प्रश्न
The electric field at a point associated with a light wave is `E = (100 "Vm"^-1) sin [(3.0 xx 10^15 "s"^-1)t] sin [(6.0 xx 10^15 "s"^-1)t]`.If this light falls on a metal surface with a work function of 2.0 eV, what will be the maximum kinetic energy of the photoelectrons?
(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)
Consider the situation of the previous problem. Consider the faster electron emitted parallel to the large metal plate. Find the displacement of this electron parallel to its initial velocity before it strikes the large metal plate.
(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)
Radiation of frequency 1015 Hz is incident on three photosensitive surfaces A, B and C. Following observations are recorded:
Surface A: no photoemission occurs
Surface B: photoemission occurs but the photoelectrons have zero kinetic energy.
Surface C: photo emission occurs and photoelectrons have some kinetic energy.
Using Einstein’s photo-electric equation, explain the three observations.
The photon emitted during the de-excitation from the first excited level to the ground state of a hydrogen atom is used to irradiate a photocathode in which the stopping potential is 5 V. Calculate the work function of the cathode used.
In \[E=h\nu\], what does \[E\] represent?
In \[E=h\nu\], what does \[h\] represent?
What condition must be met for photoelectric emission to occur?
How is the work function related to the threshold frequency \[\nu_0\]?
How can maximum kinetic energy be written in terms of stopping potential \[V_0\]?
Why does the maximum kinetic energy of photoelectrons increase when frequency increases?
