Figure represents a graph of kinetic energy (K) of photoelectrons (in eV) and frequency (v) for a metal used as cathode in photoelectric experiment. The work function of metal is

1. 1 eV

2. 1.5 eV

3. 2 eV

4. 3 eV

The graph that correctly represents the relation of frequency v of a particular characteristic X-ray with the atomic number Z of the material is

The dependence of the short wavelength limit ${\mathrm{\lambda }}_{\min }$ on the accelerating potential V is represented by the curve of figure:

1. A
2. B
3. C
4. None of these

The curves (a), (b) (c) and (d) show the variation between the applied potential difference (V) and the photoelectric current (i), at two different intensities of light ( ${\mathrm{I}}_1>{\mathrm{I}}_2$). In which figure is the correct variation shown ?

Assertion : The energy (E) and momentum (p) of a photon are related by p=E/c .
Reason : The photon behaves like a particle.

Assertion : Photoelectric effect demonstrates the wave nature of light.
Reason : The number of photoelectrons is proportional to the frequency of light.

Assertion : When the speed of an electron increases its specific charge decreases.
Reason : Specific charge is the ratio of the charge to mass.

Assertion : Mass of moving photon varies inversely as the wavelength.
Reason : Energy of the particle  = Mass$\times {\left(\mathrm{speed} \mathrm{of} \mathrm{light}\right)}^2$

Assertion : The specific charge of positive rays is not constant.
Reason : The mass of ions varies with speed.

Assertion : Photosensitivity of a metal is high if its work function is small.
Reason : Work function = ${\mathrm{hf}}_0$ where ${\mathrm{f}}_0$ is the threshold frequency