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In a photoelectric emission , from a bla...

In a photoelectric emission , from a black surface, threshold frequency is `v_0` . For two incident radiations of frequencies `v_1 and v_2` , the maximum values of kinetic energy of the photoelectrons emitted in the two cases is in the ration 1,P . If `pv_1 -v_2 =2v_0` , find the value of |p|.
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To solve the problem step by step, we will use the principles of photoelectric emission and the equations derived from Einstein's photoelectric equation. ### Step 1: Understand the Given Information We are given: - Threshold frequency: \( v_0 \) - Frequencies of incident radiations: \( v_1 \) and \( v_2 \) - The ratio of maximum kinetic energies of emitted photoelectrons: \( \frac{K_1}{K_2} = \frac{1}{p} \) - The equation relating \( p \), \( v_1 \), and \( v_2 \): \( p v_1 - v_2 = 2 v_0 \) ### Step 2: Write the Photoelectric Equation According to the photoelectric effect, the kinetic energy (\( K \)) of the emitted photoelectrons can be expressed as: \[ K = h\nu - h\nu_0 \] Where \( h \) is Planck's constant, \( \nu \) is the frequency of the incident radiation, and \( \nu_0 \) is the threshold frequency. ### Step 3: Write the Kinetic Energy Equations For the two frequencies \( v_1 \) and \( v_2 \), we can write: 1. For \( v_1 \): \[ K_1 = h v_1 - h v_0 \] 2. For \( v_2 \): \[ K_2 = h v_2 - h v_0 \] ### Step 4: Relate the Kinetic Energies From the ratio of the kinetic energies: \[ \frac{K_1}{K_2} = \frac{1}{p} \] This implies: \[ \frac{h v_1 - h v_0}{h v_2 - h v_0} = \frac{1}{p} \] Cancelling \( h \) from both sides gives: \[ \frac{v_1 - v_0}{v_2 - v_0} = \frac{1}{p} \] ### Step 5: Rearranging the Equation Cross-multiplying gives: \[ v_1 - v_0 = \frac{1}{p}(v_2 - v_0) \] Multiplying both sides by \( p \): \[ p(v_1 - v_0) = v_2 - v_0 \] Rearranging gives: \[ p v_1 - v_2 = p v_0 - v_0 \] This can be simplified to: \[ p v_1 - v_2 = (p - 1)v_0 \] ### Step 6: Set the Two Equations Equal We have two expressions for \( p v_1 - v_2 \): 1. From the kinetic energy ratio: \( p v_1 - v_2 = (p - 1)v_0 \) 2. From the given equation: \( p v_1 - v_2 = 2 v_0 \) Setting these equal gives: \[ (p - 1)v_0 = 2 v_0 \] ### Step 7: Solve for \( p \) Dividing both sides by \( v_0 \) (assuming \( v_0 \neq 0 \)): \[ p - 1 = 2 \] Thus: \[ p = 3 \] ### Final Answer The value of \( |p| \) is \( 3 \). ---

To solve the problem step by step, we will use the principles of photoelectric emission and the equations derived from Einstein's photoelectric equation. ### Step 1: Understand the Given Information We are given: - Threshold frequency: \( v_0 \) - Frequencies of incident radiations: \( v_1 \) and \( v_2 \) - The ratio of maximum kinetic energies of emitted photoelectrons: \( \frac{K_1}{K_2} = \frac{1}{p} \) - The equation relating \( p \), \( v_1 \), and \( v_2 \): \( p v_1 - v_2 = 2 v_0 \) ...
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