A particle is dropped from a height \(H.\) The de-Broglie wavelength of the particle as a function of height is proportional to:
1. \(H\)
2. \(H^{1/2}\)
3. \(H^{0}\)
4. \(H^{-1/2}\)
An electron (mass \(m\)) with an initial velocity \(\overrightarrow{\mathrm{v}}=\mathrm{v}_0 \hat{\mathrm{i}}\)
1. | \(\frac{\lambda_0}{\left(1+\frac{e E_0}{m} \frac{t}{\mathrm{v}_0}\right)}\) | 2. | \(\lambda_0\left(1+\frac{e E_0 t}{m \mathrm{v}_0}\right)\) |
3. | \(\lambda_0 \) | 4. | \(\lambda_0t\) |
According to Einstein's photoelectric equation, the graph between the kinetic energy of photoelectrons ejected and the frequency of incident radiation is:
1. | 2. | ||
3. | 4. |
Which of the following is not the property of cathode rays:
1. | it produces a heating effect. |
2. | it does not deflect in the electric field. |
3. | it casts a shadow. |
4. | it produces fluorescence. |
Which one among the following shows the particle nature of light?
1. Photoelectric effect
2. Interference
3. Refraction
4. Polarisation
A photo-cell is illuminated by a source of light, which is placed at a distance \(d\) from the cell. If the distance becomes \(\frac{d}{2}\), then the number of electrons emitted per second will be:
1. same
2. four times
3. two times
4. one-fourth
J.J. Thomson's cathode-ray tube experiment
demonstrated that:
1. | cathode rays are streams of negatively charged ions |
2. | all the mass of an atom is essentially in the nucleus |
3. | the e/m of electrons is much greater than the e/m of protons |
4. | the e/m ratio of the cathode ray particles changes when a different gas is placed in the discharge tube |
The work function of caesium is \(2.14~\text{eV}\). The wavelength of incident light if the photocurrent is brought to zero by a stopping potential of \(0.60~\text{V}\) will be:
1. \(454~\text{nm}\)
2. \(440~\text{nm}\)
3. \(333~\text{nm}\)
4. \(350~\text{nm}\)
What is the de-Broglie wavelength associated with an electron moving at a speed of \(5.4\times10^6~\text{m/s}\)?
1. \(0.244~\text{nm}\)
2. \(0.135~\text{nm}\)
3. \(0.157~\text{nm}\)
4. \(0.111~\text{nm}\)