An electrons emitter must have _______ work function and _______ melting point.

Define melting point

The material having minimum work function is

Assertion: Fuse wire must have high resistance and low melting point. Reason: Fuse is used for small current flow only.

Compounds having lowest melting point:

The collector of the photocell (in photoelectric experiment ) is made of tungsten while the emitter is Platinum having work function of 10 eV .Monochromatic radiation of wavelength 124 Å & power 100 watt is incident on emitter which emits photo electrons with a quantum efficiency of 1% .The accelerating voltage acros the photocell is of 10,000 volts (Use: hc=12400eV Å ) The minimum wavelength of radiation coming from the tungsten target (collector) is

A when a photon of energy hv is incidnet on an electron in a metal of work function phi ( lt hv) , the electron will not necesserily come out of the metal . R : work function is the minimum energy required to liberate an electron out of a metal . So some electons may require more energy for their liberation .

The crystal having highest melting point is

The potential difference that must be applied to stop the fastest photoelectrons emitted by a nickel surface , having work function 5.01 eV , when ultraviolet light of 200 nm falls on it , must be

Compound X consists of molecules. Choose the letter corresponding to the correct answer from the choices given below: X is likely to have a : [A] low melting point and high boiling point. [B] high melting point and low boiling point. [C] low melting point and low boiling point. [D] high melting point and high boiling point.

Assertion : Liquid molecules have greater potential energy at the melting point. Reason : Intermolecular spacing between molecules increases at melting point.