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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
In an experiment on the photoelectric effect, the slope of the cut-off voltage versus the frequency of incident light is found to be 4.12 × 10−15 Vs. Calculate the value of Planck’s constant.
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If c is the velocity of light in free space, the correct statements about photon among the following are:
- The energy of a photon is E = hv.
- The velocity of a photon is c.
- The momentum of a photon, ρ = `(h v)/c`.
- In a photon-electron collision, both total energy and total momentum are conserved.
- Photon possesses positive charge.
Choose the correct answer from the options given below:
