Physics Test 131

An electromagnetic waves going through vacuum is described by 

Because of the space charge in a diode valve,

A point source of light is used in a photoelectric effect.If the source is removed farther from the emitting metal,the stopping potential

A proton and an electron are acceleration by the same potential difference Let λ _e and   λ _p denote the de Broglie wavelengths of the electron and the proton respectively

Ionization energy of a hydrogen-like ion A is greater than that of another hydrogen-like ion B. Let r,u,E and L represent the radius of the orbit,speed of the electron, energy of the atom and orbital angular momentum of the electron respectively. In ground state

The X-ray beam coming from an X-ray tube

Cutoff wavelength of X-rays coming from a Coolidge tube depends on the

When an impurity is doped into an intrinsic semiconductor,the cunductivity of the semiconductor

Two identical p-n junction may be connected in series with a battery in three ways (figure). The potential difference across the two p-n junctions are equal is:

Two identical capacitors A and B are charged to the same potential V and are connected in two circuits at t= 0 as shown in figure. The charges on the

capacitors at a time = CR are, respectively,