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White light consisting of wavelengths 38...

White light consisting of wavelengths `380 nm le lambda le 750` nm is incident on a lead surface. For which one of the following ranges of wavelength will photoelectrons be emitted from the elad surface that has a work funcation `W_(0) = 6.63 xx 10^(-29) J`?

A

`380` nm `le lambda le 750` nm

B

`380` nm `le lambda le 630` nm

C

`380` nm `le lambda le 540` nm

D

No photoelectrons will be emitted

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The correct Answer is:
To solve the problem, we need to determine the range of wavelengths for which photoelectrons will be emitted from a lead surface with a given work function. The work function \( W_0 \) is given as \( 6.63 \times 10^{-29} \) J. ### Step-by-Step Solution: 1. **Understand the Photoelectric Effect**: The photoelectric effect states that for photoelectrons to be emitted from a surface, the energy of the incident photons must be greater than or equal to the work function of the material. 2. **Relate Energy to Wavelength**: The energy \( E \) of a photon can be expressed in terms of its wavelength \( \lambda \) using the formula: \[ E = \frac{hc}{\lambda} \] where \( h \) is Planck's constant (\( 6.63 \times 10^{-34} \) J·s) and \( c \) is the speed of light (\( 3 \times 10^8 \) m/s). 3. **Set Up the Inequality**: For photoelectrons to be emitted, the energy of the photon must be greater than the work function: \[ \frac{hc}{\lambda} \geq W_0 \] 4. **Rearranging the Equation**: Rearranging the inequality gives us: \[ \lambda \leq \frac{hc}{W_0} \] 5. **Calculate the Maximum Wavelength**: Substitute the values of \( h \), \( c \), and \( W_0 \): \[ \lambda_{\text{max}} = \frac{(6.63 \times 10^{-34} \, \text{J·s})(3 \times 10^8 \, \text{m/s})}{6.63 \times 10^{-29} \, \text{J}} \] Simplifying this gives: \[ \lambda_{\text{max}} = \frac{1.989 \times 10^{-25}}{6.63 \times 10^{-29}} \approx 300 \, \text{nm} \] 6. **Determine the Range of Wavelengths**: Since the maximum wavelength for which photoelectrons can be emitted is \( 300 \, \text{nm} \), we conclude that any wavelength greater than \( 300 \, \text{nm} \) will not result in photoelectron emission. 7. **Check the Given Wavelength Range**: The problem states that white light with wavelengths from \( 380 \, \text{nm} \) to \( 750 \, \text{nm} \) is incident on the lead surface. Since \( 380 \, \text{nm} \) is greater than \( 300 \, \text{nm} \), no photoelectrons will be emitted. 8. **Final Conclusion**: Therefore, the correct answer is that no photoelectrons will be emitted from the lead surface when white light is incident on it.

To solve the problem, we need to determine the range of wavelengths for which photoelectrons will be emitted from a lead surface with a given work function. The work function \( W_0 \) is given as \( 6.63 \times 10^{-29} \) J. ### Step-by-Step Solution: 1. **Understand the Photoelectric Effect**: The photoelectric effect states that for photoelectrons to be emitted from a surface, the energy of the incident photons must be greater than or equal to the work function of the material. 2. **Relate Energy to Wavelength**: ...
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