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)
A radiation of energy 'E' falls normally on a perfectly reflecting surface. The momentum transferred to the surface is (c=velocity of light)
1. E/c
2. 2E/c
3. 2E/c2
4. E/c2
Which of the following figures represents the variation of the particle momentum and the associated de-Broglie wavelength?
1. | 2. | ||
3. | 4. |
Light with a wavelength of \(500\) nm is incident on a metal with a work function of \(2.28~\text{eV}.\) The de Broglie wavelength of the emitted electron will be:
1. \( <2.8 \times 10^{-10}~\text{m} \)
2. \( <2.8 \times 10^{-9}~\text{m} \)
3. \( \geq 2.8 \times 10^{-9}~\text{m} \)
4. \( <2.8 \times 10^{-12}~\text{m} \)
Light with an energy flux of \(25\times 10^{4}~\text{Wm}^{-2}\) falls on a perfectly reflecting surface at normal incidence. If the surface area is \(15~\text{cm}^2\), then the average force exerted on the surface is:
1. \(1.25\times 10^{-6}~\text{N}\)
2. \(2.5\times 10^{-6}~\text{N}\)
3. \(1.2\times 10^{-6}~\text{N}\)
4. \(3.0\times 10^{-6}~\text{N}\)
What will be the percentage change in the de-Broglie wavelength of the particle if the kinetic energy of the particle is increased to \(16\) times its previous value?
1. \(25\)
2. \(75\)
3. \(60\)
4. \(50\)