For what kinetic energy of a neutron will the associated de Broglie wavelength be
1.40 x ${10}^{-10}$ m?

1.\(1.1 \times 10^{-2}\ eV\)
2.\(2.1 \times 10^{-2}\ eV\)
3.\(3.3 \times 10^{-2}\ eV\)
4.\(4.2 \times 10^{-2}\ eV\)

What is the de Broglie wavelength of a nitrogen molecule in air at 300 K? Assume that the molecule is moving with the root-mean-square speed of molecules at this temperature. (Atomic mass of nitrogen = 14.0076 u)

1. 0.028 nm
2. 0.031 nm
3. 0.127 nm
4. 0.0139 nm

About \(5\)% of the power of a \(100\) W light bulb is converted to visible radiation. What is the average intensity of visible radiation at a distance of \(1\) m from the bulb?
1. \(0.472\) W/m²
2. \(0.398\) W/m²
3. \(0.323\) W/m²
4. \(0.401\) W/m²

What is the de Broglie wavelength of a bullet of mass \(0.040\) kg traveling at the speed of \(1.0\) km/s?
1. \(1.65\times10^{-35}\) m
2. \(1.05\times10^{-35}\) m
3. \(2.15\times10^{-35}\) m
4. \(2.11\times10^{-35}\) m

 An electron and a photon each have a wavelength of 1.00 nm. The momentum of the electron will be:

1. Greater than photon.
2. Equal to the photon.
3. Less than photon.
4. None of these.
 

The work function of cesium metal is \(2.14\) eV. When light of frequency \(6\times10^{14}\) Hz is incident on the metal surface, photoemission of electrons occurs. What is the stopping potential of the metal?
1. \(0.212\) V
2. \(0.345\) V
3. \(0.127\) V
4. \(0.311\) V

The photoelectric cut-off voltage in a certain experiment is \(1.5~\mathrm{V}\). What is the maximum kinetic energy of photoelectrons emitted?
1. \(2.1 \times 10^{-19} \mathrm{~J} \)
2. \(1.7 \times 10^{-19} \mathrm{~J} \)
3. \(2.4 \times 10^{-19} \mathrm{~J} \)
4. \(1.1 \times 10^{-19}~\mathrm{J} \)

Monochromatic light of wavelength \(632.8~\text{nm}\) is produced by a helium-neon laser. The power emitted is \(9.42~\text{mW}\). The energy of each photon in the light beam is:
1. \(4.801 \times 10^{-19}~\text{J}\)
2. \(2.121 \times 10^{-19}~\text{J}\)
3. \(5.043 \times 10^{-19}~\text{J}\)
4. \(3.141 \times 10^{-19}~\text{J}\)

The energy flux of sunlight reaching the surface of the earth is \(1.388\times10^{3}\) W/m². How many photons (nearly) per square meter are incident on the Earth per second? Assume an average wavelength of \(550~\text{nm}\).
1. \(3.84\times10^{21}\)
2. \(2.97\times10^{21}\)
3. \(4.12\times10^{21}\)
4. \(2.10\times10^{21}\)

In an experiment on the photoelectric effect, the slope of the cut-off voltage versus frequency of incident light is found to be $4.12\times {10}^{-15} V s$. The value of Planck's constant is:

1. $6.682\times {10}^{-4} Js$
2. $6.592\times {10}^{-34} Js$
3. $6.621\times {10}^{-34} Js$
4. $6.502\times {10}^{-4} Js$