Select Chapter Topics:

An electron of mass m with an initial velocity \(\vec v= v_0\hat i\)$\stackrel{}{}$\( ( v_o > 0 ) \) enters in an electric field \(\vec E = -E_0 \hat i\)\((E_0 = \text{constant}>0)\) at \(t=0\). If \(\lambda_0\)${\mathrm{}}_{}$\(\lambda_0\)

1. \(\frac{\lambda_0}{\left(1+ \frac{eE_0}{mv_0}t\right)}\)

2. \(\lambda_0\left(1+ \frac{eE_0}{mv_0}t\right)\)

3. \(\lambda_0 t\)

4. \(\lambda_0\)

Subtopic: De-broglie Wavelength |

67%

From NCERT

NEET - 2018

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

Hints

Links

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

When the light of frequency \(2\nu_0\) (where \(\nu_0\) is threshold frequency), is incident on a metal plate, the maximum velocity of electrons emitted is \(v_1\). When the frequency of the incident radiation is increased to \(5\nu_0,\) the maximum velocity of electrons emitted from the same plate is \(v_2.\) What will be the ratio of \(v_1\) to \(v_2\)?

1. | \(1:2\) | 2. | \(1:4\) |

3. | \(4:1\) | 4. | \(2:1\) |

Subtopic: Einstein's Photoelectric Equation |

72%

From NCERT

NEET - 2018

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

Hints

Links

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

What is the de-Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T (Kelvin) and mass m?

1. $\frac{h}{\sqrt{mkT}}$

2. $\frac{h}{\sqrt{3mkT}}$

3. $\frac{2h}{\sqrt{3mkT}}$ $$

4. $\frac{2h}{\sqrt{mkT}}$

Subtopic: De-broglie Wavelength |

80%

From NCERT

NEET - 2017

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

Hints

Links

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

The photoelectric threshold wavelength of silver is \(3250\times 10^{-10}~\text{m}\). What will be the velocity of the electron ejected from a silver surface by the ultraviolet light of wavelength \(2536\times 10^{-10}~\text{m}\)? (Given \(h= 4.14\times 10^{-15}~\text{eVs}\)$$ and $\mathrm{}$\(c= 3\times 10^{8}~\text{m/s}\)${\mathrm{}}^{}$)

1. \(\approx 0.6\times 10^{6}~\text{m/s}\)

2. \(\approx 61\times 10^{3}~\text{m/s}\)

3. \(\approx 0.3\times 10^{6}~\text{m/s}\)

4. \(\approx 0.3\times 10^{5}~\text{m/s}\)

Subtopic: Einstein's Photoelectric Equation |

From NCERT

NEET - 2017

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

Hints

Links

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

If an electron of mass m with a de-Broglie wavelength of \(\lambda\) falls on the target in an X-ray tube, the cut-off wavelength ( λ_{0}) of the emitted X-ray will be:

1. ${\lambda}_{0}=\frac{2mc{\lambda}^{2}}{h}$

2. ${\lambda}_{0}=\frac{2h}{mc}$

3. ${\lambda}_{0}=\frac{2{m}^{2}{c}^{2}{\lambda}^{3}}{{h}^{2}}$

4. ${\lambda}_{0}=\lambda $

Subtopic: De-broglie Wavelength |

From NCERT

NEET - 2016

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

Hints

Links

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

Photons with energy 5 eV are incident on a cathode C in a photoelectric cell. The maximum energy of emitted photoelectrons is 2 eV. When photons of energy 6 eV are incident on C, no photoelectron will reach the anode A, if the stopping potential of A relative to C is:

1. +3 V

2. +4 V

3. - 1V

4. -3 V

Subtopic: Einstein's Photoelectric Equation |

51%

From NCERT

NEET - 2016

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

Hints

Links

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

An electron of mass m and a photon have the same energy E. Find the ratio of de-Broglie wavelength associated with the electron to that associated with the photon. (c is the velocity of light)

^{$1.$ ${\left(\frac{E}{2m}\right)}^{1/2}$$$$2.$ $c{\left(2mE\right)}^{1/2}$$$$3.$ $\frac{1}{c}{\left(\frac{2m}{E}\right)}^{1/2}$$$$4.$ $\frac{1}{c}{\left(\frac{E}{2m}\right)}^{1/2}$}

Subtopic: De-broglie Wavelength |

59%

From NCERT

NEET - 2016

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

Hints

Links

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

When a metallic surface is illuminated with radiation of wavelength \(\lambda\), the stopping potential is \({V}\). If the same surface is illuminated with radiation of wavelength \(2\lambda\), the stopping potential is \(\frac{{V}}{4}\). The threshold wavelength for the metallic surface is:

1. \(5\lambda\)

2. \(\frac{5}{2} \lambda\)

3. \(3\lambda\)

4. \(4\lambda\)

1. \(5\lambda\)

2. \(\frac{5}{2} \lambda\)

3. \(3\lambda\)

4. \(4\lambda\)

Subtopic: Einstein's Photoelectric Equation |

76%

From NCERT

NEET - 2016

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh

Hints

Links

To view explanation, please take trial in the course.

NEET 2023 - Target Batch - Aryan Raj Singh