Medicine

A particle is dropped from a height H. The de-Broglie wavelength of the particle as a function of height is proportional to  (a) H  (b) H^1/2 (c) H⁰   (d) H^-1/2

Consider a 20 W bulb emitting light of wavelength 5000 Å and shining on a metal surface kept at a distance 2 m. Assume that the metal surface has work function of 2 eV and that each atom on the metal surface can be treated as a circular disk of radius 1.5 Å.
(i) Estimate number of photons emitted by the bulb per second. [Assume no other losses]
(ii) Will there be photoelectric emission?

(iii) How much time would be required by the atomic disk to receive energy equal to work function (2 eV)?
(iv) How many photons would atomic disk receive within time duration calculated in (iii) above?
(v) Can you explain how photoelectric effect was observed instantaneously?

A particle A with a mass m_A is moving with a velocity v and hits a particle B (mass m_B) at rest (one dimensional motion). Find the change in the de-Broglie wavelength of the particle A. Treat the collision as elastic.

A student performs an experiment on photoelectric effect, using two materials A and B. A plot of V_stopversus v is given in figure. Which has higher work function?

Consider an electron in front of metallic surface of a distance d. Assume the force of attraction by the plate is given as $\frac{1}{4}\frac{{\mathit{q}}^2}{4\mathit{\pi }{\mathit{\epsilon }}_0{\mathit{d}}^2}$ . Calculate work in taking the to an infinite distance from the plate .Taking d=0.1 nm. find the work done in electron volts?