The stopping potential as a function of the frequency of the incident radiation is plotted for two different photoelectric surfaces A and B. The graphs show that work function of A is 

(1) Greater than that of B
(2) Smaller than that of B
(3) Equal to that of B
(4) No inference can be drawn about their work functions from the given graphs

The graph between intensity of light falling on a metallic plate (I) with the current (i) generated is

For a photoelectric cell the graph showing the variation of cut of voltage (${\mathrm{V}}_0$) with frequency (v) of incident light is best represented by

The correct curve between the stopping potential (V) and intensity of incident light (I) is

The value of stopping potential in the following diagram

(1) – 4V
(2) – 3 V
(3) – 2V
(4) – 1 V

In the following diagram if ${\mathrm{V}}_2>{\mathrm{V}}_1$, then,

(1) ${\mathrm{\lambda }}_1=\sqrt{{\mathrm{\lambda }}_2}$

(2) ${\mathrm{\lambda }}_1<{\mathrm{\lambda }}_2$

(3) ${\mathrm{\lambda }}_1={\mathrm{\lambda }}_2$

(4) ${\mathrm{\lambda }}_1>{\mathrm{\lambda }}_2$

A parallel beam of light is incident normally on a plane surface absorbing 40% of the light and reflecting the rest. If the incident beam carries 60 W of power, the force exerted by it on the surface is

(1) $3.2\times {10}^{-8} N$

(2) $3.2\times {10}^{-7} N$

(3) $5.12\times {10}^{-7} N$

(4) $5.12\times {10}^{-8} N$

Assertion : The de-Broglie wavelength of a molecule varies inversely as the square root of temperature.
Reason : The root mean square velocity of the molecule depends on the temperature.

In X-ray tube, the accelerating potential applied at the anode is V volt. The minimum wavelength of the emitted X-ray will be :

(1) eV/h

(2) h/eV

(3) eV/ch

(4) hc/eV